It depends. If you really want TM, then you just wait what it takes. I've ordered stuff knowing it won't be done for 6 months. Heck, my officer took a year. It really depends on what you want.
Also, there are other aspects. How cheap it is to get replacements? ATA is pretty cheap if you need a new butt plate for instance and turns those around fast. RT does replacements relatively quick but aren't really cheap. Plus, there is location. If I have a problem with an RS or TM suit, I'm pretty much stuck being here in the US compared to ATA or RT. People in the UK and EU seem OTOH seem to do better by TM or RS.
So - no one right answer - everyone has to pick what is best for them.