Having owned an SA-5000 in the past and having compared it to one of the earlier First Sound Presence models, I can tell you that the First Sound IS in another league altogether. The Presence had better dynamics, resolution, imaging, and sounded so much more natural; more at ease. The Presence did have NOS 6DJ8's in it, Amperex Gold pin/D getter, if memeory serves me. I can't remember which tubes I'd had at the time in my Counterpoint. I think Gold pin Amperex's.
My SA-5000 saw the shop a few times before I'd owned it and once in the brief time I'd owned it. I horse traded the Counterpoint off years back, demo'ed a Tube Research GTP-3 and bought it.
If you are limited to chose between only the SA-5000 or the First Sound, definitelly listen to the First Sound. If you are not limited to those units only, check out the Tube Research. The prices of the TRL GTP-3 and the FS Presence are pretty close to each other.