I'd be more concerned with torque than HP running through it.
And as Chris and others said, it's a total crapshoot. There are too many other variables (E.g., look at Chris's 60' - he was haulin, which = tons of torque).
As you know, doing things like keeping the traction or clutch as the fuse in the driveline can help (organic disk, a non-ubergrip PP, etc).
It seems to me that once a sticky clutch and slicks go on, all bets are off.
My 93 lx was making 390+rwhp and 380+rwtq and with Original 124,000 mile clutch handled it like a champ. Probably even survived the drunk that hit it at car show and killed off the car.
I run the stock T5 with about 180,000 miles on it and for the last year I have had the 347 with a 100 shot of juice. I won't power shift though.
But like already mentioned: sticky tires and a grippy clutch means the tranny is the weakest link. I've seen em last when they shouldn't and I've seen em go for no reason.
I'll let you know as soon as I hook u pmy nitrous, lol. I am at or just beyond 300rwhp to dyno soon. I know because I was close to 300 before I did my recent mods. It's fine. I think the key is that I don't powershift but also that my traction of lack of and NON beefed up rear suspension allows some play so it don't breaky.
After my nitrous I will be doing no powershifts, no slamming the clutch, no nitrous in first or second. After I get the new trans, all bets are off and I would like to manually blow it up for fun!
Gears have an effect on it too, I believe. Run high horse on sticky tires with grippy clutch PLUS stock gears, and BANG. All the more reason not to fear the gear.