All plastic mounts 7/8 use the same motor adapters.
Mini-z started as a way for kyosho to increase the market of their static models. If you could take the beautiful die cast model look, and actually drive it thre is more appeal.
I believe the mr01 was available before the xmod, which was originally designed for radio shack by HPI, and built to a price.
I have had some long debates with mleemor about the current and future state of the mini-z. I personally am in favor of the new technology, of brushless and lipo... however, one major point that always comes up that I wholeheartedly agree with, is that the newer tech is simply too fast for good racing.
this scale is best raced between the AAA 70t stock speed and AAA 50t speed. Faster than that, you really need alot of experience, setup knowledge, and reflexes to keep up with the car.
if slower motors can be designed, say a 2300kv, to run 2S and have a similar speed to a 70t on AAA, then moving forward could be much easier.
while I am not a mini-z purist so to speak, there are MANY things that kyosho did right. And by keeping the cars on AAA with their mabuchi white motor, it has kept the point of entry consistent speed wise amongst all of it's brushed offerings.
The limitation that we have right now, is more on the motors than on battery tech. The 130 brushed motors are all too fast 2S, and have durability concerns due to heat above 6v. 1S would be a more viable option, but the electronics would need a redesign to include a voltage booster for the RX and servo to maintain the quality of steering need at this scale.
having worked with not so local tracks in trying to best organize class structures, it is not easy to try to balance the power amongst old and new tech.
the only true raceworthy motor on 2S is a 3500kv motor, while mathematically similar to 5600kv or a 50t on AAA, there is a lot more bottom end with the 3500kv on 2S... they will top out at similar RPM, but acceleration out of the corners is completely different.
until motor tech can really catch up, it will be difficult to impossible to race them together. So, stock classes will be best suited to the mini-z, and mod classes dominated by the lipo aftermarket machines.
I raced with the legendary Joel Johnson once, and he couldn't keep up to a modified mini-z, but had a blast trying. That was a AAA car... fast forward to today, and it would really be difficult when one trigger pull is all that is needed to fly off the track.
I see mini-z making a rise again, but in order to have good racing the speeds must remain stock to pro stock.
the only real negative to using AAA is the maintenance required to keep them performing. I currently only use eneloop cells since they store well. Which is important to me due to my intermittent race schedule. The cells are slower, with a little less punch out of the corners and a lower amperage limit, but for 70t to 50t motors, you really don't need moreto be competitive. Mod motors that pull more than 1.5A, tend to overheat the cells and drastically reduce performance. I just don't have the time to cycle cells.