It depends on what you want. The older Bryston amps will have a nice smooth sound, but they can sound dull. They are definitely not fast amps. The ST series (gen 2) did improve things and the SST series (gen 3) was even faster and brighter. The Bryston amps can be on the sterile side, depending on how you use them.
If you are comparing the 7B-ST to a newer Emotiva XPA-1, the Emotiva will be significantly faster and quicker in the response. Stock, the Emotiva will have a digital/solid-state type of signature until you upgrade the fuses. I would recommend a Furutech/Isoclean combination for the fuses, or just try with straight Isoclean first.
Like stereo5 said, 16 years is a very long time for the amp and re-capping is pretty much a requirement if you want good sound. Sure, Bryston will still warranty this amp up to 20 years, but caps still age.