As for MST: MST is a team that pretty much stops ground rushing. With Tron in the way, it gets very difficult to come in from the ground offensively, since if you don’t block you’ll probably eat the two rings [or worse, the 3rd glitched one]. Trons assist is weird, you can use it to your advantage. If you dash in and stop JUST outside of normal assist range, i.e. Commando/Psy and call her out, you will most like rape and stuff the other assist before they can do anything.
Assist killing is one of MSTs strengths. Simple things to do, like trapping the opponents assist between tron and your point character, do extremely heavy damage. If the opponent is being defensive, and calls out an assist, simply countercall. Call tron out after their assist is done with their shit, then nj over their assist, sandwiching them. This will ensure that they get hit with all three rings, doing stupid damage. After one or two reps of that, they’ll have to play more cautiously, or else they’ll be playing a 2 person team.
C.lk + tron c.lk sets up a lot of stuff, especially if their in the corner. If they pushblock, most likely they’ll pushblock you, but tron will STILL be there and they’ll be in so much blockstun that you’ll have more than enough time to come back in and start up your rush [remember that their assist can’t come out and save them in this situation].
C.rh + tron sj. XX is what you can also do to their assists. This gives you a bunch of options. You can 1) do a SJ trijump RH and block or 2) do a SJ trijump RH and then another c.RH, which leaves to massive assist damage or 3)do nothing but SJ and airdash forward, taking the momentum.
Trons’ blockstun allows you to get at least 2 or 3 trijumps in, it’s just THAT long. Build two meter and punish assists and try to cover Tron with random tigerknee’d EM disruptors. If you have two meters and you see that they’re going to punish you the next time you to that, depending on the character, you can get them straight into the infinite. If storm does a typhoon XX hail to punish you [provided that Sent is NOT the character tron is raping] you can TG EM disruptor XX tempest XX DHC.
As Reset said, it’s a fun team, but is pretty gimmicky. You have to have a very good solo Mag, since tron pretty much forces/allows you to play 1 on 1, point character vs point character. If your Mag gets killed and you wind up playing against Sent/Capcom, you’re in for a tough fight. Storm/Tron isn’t too bad, but against Sent/Cap, it’s not very good at all. Beam XX fly will prevent most Commando punishing, and he can countercall as well. Tron stays out for a long time after her assist is done, and Cap + flying FP or whatever hurts. 
There is a ton of stuff left to talk about, I’ll try to get to the rest of MST and answer the other questions in the thread. :karate: