Okay so here's be being a newb again, help me out. I understand the difference in motors. Depening on # of turns, or nowadays KV rating, tells you the size of the motor. Somehow certain motor's outperform others, even with the same # of turns. Thats JFM. (just magic). Here is where I get a little lost.

Sensored? I have no idea......What for? why?

Speed controls....Im guessing the more you spend the more adjustments you get....?

Reason I ask is essentially all Speed controls perform the same job. But with the varitety of classes, manufactures are putting out specialized speed controls by class now.

So what's the difference between a speed control by the same Manufacturer....just the programming options?

I guess im not buying the marketing for setups.....I purchased the Novak Havoc, Ballistic motor. But you can run that motor in anything.....What makes that ESC a SC speedo?

Okay, so ive rambled enough.....

sensored, u need to connect a sensor cable from your esc to motor. it helps the esc to know the position of the rotor for control..

speed control, it adjust the amperes to the motor. more current higher rev.. braking & reverse are part of the task of esc... for the pro spec esc they do not have reverse function..except forward throttle & brakes.

most esc does the same function, some u need use sharp object to poke like the lrp esc for setup & program.. while other they give u option of program card which rather interactive. the choice of esc depends on each individual requirements, availability & support.

Send me the next layer of information that follows this up....maybe I sold myself short on the newb.

So....A certain ESC could get more perfomance out of a motor than another ESC.

Does the sensored motor limit your ability to swap out motors. A tekin ESC, and a Novak motor?

Some sensored ESC's NEED a sensor wire plugged in from the motor to work, others don't. Tekin's for example can run sensored or sensorless, where as others can't.
ESC's all have FET's that control the power output. The quality and quantity of the fet's, along with other circuitry determine the efficiency of the ESC. The more efficient, the less heat build up and greater power flow to the motor.
ESC's don't send power to the motor, rather the motor draws power through the esc, so that is why ESC's have a motor turn limit.
To a point you pay more for quality, but some of the new stuff Hobbywing does is on par with the top stuff. Why?, well they are the same as Speed Passion for a start, just different label (therefore developed for competitive racing), also they don't have all the features like running sensorless, or brushed motors.
Programming is important if you are serious about racing, but if you're out to have fun, or spec racing, extra's are often not necessary

Well, After jumping head first into SC, ive found an Oval car. Needed another class to run in and budget wasnt to the TC level. I would be nice to kind of have a system that you could interchange. If buget allowed it would be nice to have a backup or two. Or worse case senario, be able to pull from one car to setup another. But I dont know whats considered a Off-Road/Touring/Oval....stuff.

My Havok ESC/Ballistic doesnt care what car its in?

Ive heard the GTB is still a good ESC, and does both Brushed/brushless.

Any other ESC's that are as versatile? Or more versatile than another.

You will have to see what the class rules are for SC and Oval in your local area. I believe most oval racing is not 2-cell, but may be wrong.
The gear you mentioned can't do single cell lipo, or 4-cell NiMh. The GTB goes fine, but is not really a race spec.
I use Tekin, and their esc's are second to none. The RS and RS Pro can do brushed, brushless, 1 cell or 2 cell lipo, any NiMh from 4 cell up, and the Hotwire interface is easy to follow.
Many racers still use older and lower spec gear, and have fun doing it. THe only problem is, when you need a specific application (like single cell lipo), you need to go out and get new gear.
If you are budet concious, look around for some top-line 2nd hand gear. If you aren't budget conscious, just get the top stuff straight off.
THere is always a bit of $$ paid for marketing by the big companies, but if they were no better than the cheap stuff, don't fool yourself into thinking you will be the first person to find out, because many have looked into it before

Another feauture that has not been brought up for the sensored ESC's is "boost" or the ability to electronically tune the motors timing in realation to its RPM's thus increasing performance. Although alot of SC stock classes are banning this function it does allow you to extract a noticable increase in performance from a 17.5 or 13.5 brushless motor.

I too run Tekin, in fact they developed the first programable ESC WAAAAY back when. I have the RS model and it has been great, not to mention their customer service is fantastic.

I can't answer all your questions, but I can answer the question about sensored vs. non-sensored. The higher KV motors can be prone to cogging with sensorless, and in general a sensored motor is smoother throughout the powerband, especially down low. There are some escs that work in sensored mode down low, then switch to sensorless up high to increase efficiency.
Why one esc is an "SC" model vs it's regular version I'm not quite sure, although the SC version tends to be able to handle 550 size motors, and perhaps has better heat control for the greater loads put on it. Don't quote me on that, since I'm kind of asking the same question elsewhere (can the GTB handle a 550 motor?) in this forum.

The Speed Passion GT series can run unsensored. But starting with version 2.0 they don't do brushed, that's correct.

One of the best all-around, affordable escs (if you do not need/want timing adjustments) is our old workhorse GTB---soon to be replaced with the highly upgraded GTB2. The GTBs are sensored only, with very low on-resistance (for cool running/high performance) with a low 3.5T 540 motor limit and a 4.5T 550 motor limit.

Our web-site has a lot of information if you want to do some reading :

Technical Info Updates

This list has an article discussing the differences between sensored and sensorless escs.

We will not be including the brush mode in any new BL controllers; we included it initially during the transition from brush to brushless.

Not really magic at all.

It's all about efficiency. A motor is a machine designed to take electrical energy, and turn it into mechanical energy (in this case rotation, torque). Ideally a motor would convert 100% of the electrical energy into mechanical, but that is not possible. Some of that energy is lost (mostly as heat).

Some lower quality motors might only be 70-80% efficient. Some high quality motors might approach 95%+. Every percentage point can make a big difference. It all depends on the design, materials used, quality of build. That's why there can be a big difference, even if both motors have the same number of turns or same kv.

There is a reason why you can buy a cheap Feigao-style 540XL motor for $50, and a Castle/Neu costs $150. The Castle/Neu uses higher quality components, better mechanical and magnetic design, and is overall a more efficient motor. It does a better job at taking that electrical energy and putting it to the wheels of your RC, instead of turning it into heat, which is your motor and ESC's biggest enemy.