At 400+hp, What kills A904s?

Finally somebody mentioned an actual cost with a list of upgrades!! Under $1,000, race prepped case, 6 disc direct, 5 disc forward, billet servo, TA FMVB, deep pan; EXCELLENT! What would the cost be with today's prices? $1,500? OP, do you want to spend $1,500 on parts for your trans? Let's say it will save you 1/4 second in the quarter...worth it? You can slap a cheap kit into a 727 and it's STRONGER.