I own a B100R, a PF500, and a few other Ampegs, including a 63 B15. I'll probably get bagged on for this, but IMO - I'd go get your SVT-350. It's a proven design, and if it's served you well all this time you know it's dependable. I wouldn't ditch it for a PF500. I've had three PF500's go up in smoke so far, and honestly I don't trust it to take to a gig. As far as comparing the PF500 to the B100R - the two are very different despite "looking the role". The B100R actually sounds louder, and has more room filling low tones - where as the PF500 sounded tighter, and weaker in an A/B comparison. I had to cut ports in one of my PF cabs to get it to sound closer to the B100R. The porting did help quite a bit, but the nod still goes to the B100R.
I play bass - not treble!
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