RMMs are pretty much essential on these cars. Even at stock power levels, the engine flexes a lot. Once you get some mods/tune/make solid power gains, I've actually heard of people having their engine bang against the firewall because of the stock RMM's weakness in conjunction with the extra twisting force on the drivetrain.Installed CS RMM inserts last night. Compared to a CPE-Stage 2, there are only 1/4 of the idle vibes. No added vibes while cruising or decelerating. Initial clutch slip to get the car going has a rougher feel, but still about a 1/4 of the vibes I experienced from the CPE-Stage 2. There is still pretty much the same engine growl on startup that I experienced with the CPE-stage 2. Which is awesome.
The butt dyno feels a bit more pep on initial acceleration through any gear. The engine feels like there is about 2/3rds less movement on shifts and throttle blips. This is enough to satisfy anyone who just wants to rid the normal drive experience of the floppy shifts/engine movement in this car.
Any of you that have been following this thread know that I've been constantly aggravated by poor shifting performance and transmission feel in this car. So far the inserts offer the best trade-off between transmitted gear/shift noise and improvement in shift feel. I feel like my transmission is shifting right in the pocket now, at least for my liking. But with this said, I've only driven the car in 74 degreeish weather and the shifts get real shitty at higher and lower temps. This afternoon should be a good litmus test.
For the daily driver, who wont be rampaging through gears like a 600lb gorilla, the inserts are probably more than enough for satisfaction in engine movement control and comfort. If I was making more power, I'd probably go back to the CPE-Stage 2, but for now, these are great. I'm sure they will loosen up slightly after being worn, but I'm not expecting too much loosening of the feel because I really don't drive the car very hard or pound through gears.
The install was more annoying than putting in a full replacement. The inserts make stuffing the stock RMM back in the car a miserable chore for anyone laying on their back with the car on jack stands. I had to get creative and put a cloth on the end of a socket wrench extension, stick it in the open side of the RMM and pound it in with a hammer. Then wrestle the damn thing to turn it and line it up perfectly to get the bolts in and line up the transmission bracket completely. I did this install/unistall 3 times with the CPE-Stage 2 and it was never such a pain in the ass. The inserts add about a little over a 1/4" of thickness to the stock RMM.
For a regular Joe, who doesn't wrench very often, a job that took me 30 minutes with the CPE-Stage 2, ended up taking me 2 1/2 frustrating hours with the inserts and I've got bloody knuckles, a bruised back and a sore neck. Therefore, for the regular Joe, I recommend only taking your own time to install these if you have a lift. No lift? Save yourself the pain and anguish and have a shop do it, unless you love frustrating, soul sucking, time wasting challenges.
To improve shifting performance, the TMM seems to be the best bet. Makes perfect sense, since it is anchored to the transmission. Nothing like immobilizing the transmission to make shifting more accurate. Again, the need to do so will increase proportionately with your power level, which directly impacts how much things want to move around under the hood when you go wide-open throttle. But the TMM is known to transmit transmission whine and clutch-out chatter. It's a trade-off. My Damond TMM doesn't do this too much, but you can definitely notice it. Other mounts I've heard in person transmitted much more NVH.
Since I'm at ~385/380 in good weather, I ended up going fully mounted and I couldn't be happier in terms of amazing performance and moderate NVH. If you think the RMM makes it feel like the engine moves a lot less, just wait until you get a 2nd or 3rd mount in there - it is a VERY noticeable improvement over just RMM.