Build a 904 or buy one off the shelf?

I just got my 904 rebuilt for $976. It was completely disassembled and cleaned, all rebuilt with a shift kit and bolt in sprag and they painted it. The builder says it should handle 500hp. My 318 only makes about 100hp lol. I heard to many bad things about TCI on various sites plus my buddy had one in his roadrunner and it was never quite right.