Just don't sidestep the clutch. I've never broken anything launching and I used to launch on the street all the time just for the fun of it. In fact the two times I've broken my tranny it was in normal street driving and me doing something stupid. One was having a tranny bolt snap, killing the clutch and driving it home clutchlessly. At the time I didn't know about starting the car in gear, so when I got stuck at a red I tried to just jam it in first and broke a shift fork, still managed to limp it home. Second time, I was driving without the clutch again (I just noticed this trend... hmm), this time for no reason other than for the fun of it. It was going fine but I got lazy after a while and tried to just lightly toss it into third. With my shifter setup you have to firmly hold it against the gear until it slides in. It bounced right off of third with a horrible GRUNCH and hasn't been the same since, which is why my third grinds at high rpm and I have to tear my tranny down to replace the synchro. Why I was doing this with a crappy DSM tranny and crappy cable-shifter setup I cannot say.

Cliff's notes: Slip your clutch out smoothly on an AWD launch. That's always given me better 60's than dumping it, and dumping it always gives me wheel hop and tends to break things. Also, don't drive without the clutch without a good reason (Probably only a problem for weirdos like me...).