In terms of reliability, does the Antminer T9 require less repairs than the S9?
it is never about repair, it is about usage.
Keep it cold and dry and it should last for a year.
I don't know, with bitmain equipment you certainly have to factor in failures. Every piece of equipment I've owned since my first 4 S5s have been in a professional cold data center and I've had a 30% failure rate with S9s. The S7s were slightly better but not by much. I can't imagine how bad it would have been if they hadn't been cold and dry the whole time. Now, my Avalon equipment has been nothing but reliable with no failures as a frame of reference.
I have no experience with the T9 but they are also made by bitmain...