I am currently using Spektram DX2S for Onroad(17.5 blinky).
Quite few guys at track told me that other better radios gives better response in handling.

I started to look at few options for my future wish list(depends on what my wife will say ok or not).

- Futaba 4PL, 4PKS
- Airtronic(Sanwa) M11x, MT4
- KO new EX1(when it comes out in US)

My car needs 2ch to control(Onroad EP) but most of these "Good" radios comes with 4ch which I do not think I need them for EP RC car. Most of these god radios seems to come with more than 3 r 4ch. Is there any good racing quality radio with 2ch? or most of these guys racing at track utilize more than 3ch to control their cars beyond my knowledge?

Thanks in advance for your comment!

you need a radio where both transmitter and receivers are fast and exact. I'd recommend the Sanwa brand. as for the number of channels, no, you're not going to need 3 channels for EP on-road racing. but the functions that are the most important (expo for all servo curves, subtrim, servo speed, EPAs for all servos) in a radio are available on radios that have at least 3 channels. so just ignore the number of channels and focus on features.

Thanks for your advice!
I look into functions now. Sanwa, futaba and Ko were recommended by few of my fellow racers.

I have a 4PKS and love it. It replaced my 3PKS which my son uses now. Either radio is great, The M11x is also a great radio, I had a M8 years ago and it was a solid TX, the M11 platform is proven and reliable. You can't go wrong with any of these. I've had great luck with Futaba, I have owned every one of their top radios over the past 25 years and have never had one fail. My circa 1990 3PB PCM radio still works perfectly with some of our vintage cars as does our 3PJS circa 1998. The Futaba 4PL is nice but has higher latency than the M11x or 4PKS.

Dont think you can go wrong with any of the brands you mention. An important factor is how well it balances and feels in your hand. Also, it dont sounds like your current radio is bad or something, so if you dont have a fast steering servo, I'd start with that, and get the radio later on. Likely, wifey wont recognise that you got a new servo

My current serve in a XP DS1015.
I believe that this is a digital servevo..
To obtain full benefit of M11x, MT4, 4PLs, should I consider to have new servo?

I was new for this hobby a year ago when I purchased my current setup(TC6, Tekin RSPro, 13.5 and DS1015), I just followed a recommendation of the Hobby shop. Then I really got into this hobby and learnt a lot(Like I should have got 17.5 motor first, Did not need RS pro for blink race, etc).

Now my TC 6 has RS pro +17.5 and Myself started to lap without crashing. I do not have any issue with Spektram DX2S except I sometime encounter interferance when the track is really busy requires re-binding.

I do not think my stearing is pro-level fast demanding fast, but my birthday is coming up so I may have once a year opportunity to overcome toughest negotiation with my only race team sponsor(Company called W.I.F.E inc)

I would recomment you 1st step has to be a set of BLS servos and then the transmitter!!
Go with sanwa if your pocket has less, is awesome radio!

Thanks for all the info!

The XP DS1015 seems quite decent - brushless and speed about 0,1 sec @ 60 deg. It exists in two versions though, at the end of this post, there's a copy of features/specs.

Anyway, I think I read somewhere that the KO TX's require KO RX + KO servos to get the ultimate response. But I'm no expert about this, so I suggest that you dig into the details, before deciding - total budget for servo, eventually extra RX's and TX might be a factor too

Specs & info from www.cmldistribution.co.uk :

Available in two versions, Team Associated’s XP Digital Servos feature many enhancements that improve vehicle control and on-track performance. Equipped with an all-new ultra-precise metal gear and an advanced microprocessor, the XP Digital Servo provides precise outputs and ultra fast signal response. The state-of-the art aluminum heat sink mid case lowers operating temperatures for fade-free performance.

Features

Water and dust resistant
JR type connector
Aluminum heat sink case
Coreless motor
Equipped with ultraprecisemetal gears

Advancedmicroprocessor that processes signals faster and with
more precision

Advanced case design enhances structural integrity
Higher holding power with fewer angular errors
Superior torque output with low current consumption


Spec Check
Dim. (LxWxH)mm: 41.8 x 20.6 x 39.6
Weight (g/oz): 66 / 2.328
Torque (Kg-cm/oz-in) @ 6V: 14.5 / 201.4
Transit Time (sec/60°) @ 6V: 0.108
Voltage Range: 4.8 – 6V

just a quick note on servo speed: I used the AE XP3-SS set for about a year or so, that's a low budget 2.4GHz set, rebadged from Futaba. I always thought I could need faster servos, when I looked at the other cars of the buddies my steering seemed very sluggish.

But recently I bought the MX-3X from Sanwa, and WOW! I had to find out, that my servos are indeed faster than I thought. It turned out it was the radio that wasn't pushing those to the limit (mind you, these are all noname servos, like BlueBird and HXT)

As for 17.5 onroad, any metal gear servo would do fine, that can achieve about 0.1sec at 6V. If it's faster, even better, you'd be able to tune its speed down with a good transmitter (like those from Sanwa). if you go for the Sanwa, the 92744 (or RX-451) receiver should do just fine, even the pros don't run the high speed versions of those RX's.

Don't forget about the new radiopost transmitter held one a few weeks ago and I was super surprised so surprised I was offered sponsorship moving away from futaba 4pk for this season. I've been futaba for many years something just felt so right the feel was better. If you have a chance hold one and you will see what I'm talking about.

There's a few offers super nice case, transmitter, 5 channel receiver for 280.00 you can't beat the deal plus you get a wicked case like the futaba super for http://www.trick-parts.com/product_p/ts401c.htm

I probably will keep current DS1015 XP servo at this moment since the spec looks ok for now. At least for my purpose.

I am moving from Spektrum DX2S that was I believe good radio for me and had no issues unless I had to re-bind when track is really busy(at off-road side).

I do not know what to expect yet if I move to Futaba 4PL or Sanwa M11x/Futaba 4PKS from DX2S. Pricewise, Futaba 4PL has good value to me and easier to negotiate with my department of Treasury

Since this will be my second radio in my hobby life so never experienced "improved" feeling due to radio change.

I know these 4PKS and M11x must be so well made judged by their price. I hold 4PKS today at LHS and that was so well built compare to 4PL and even M11x.
I read through some similar topics in other thread so I refrain from making same questions but your commits are so welcome on these radios that my candidates.

Thanks for all your advice.
I decided to go with M11x. Started to setup for my first day with it on track.