I think that one of the things that are underappreciated in these discussions is that if we talk about breakup, ANY tube amp is “too much” for home use. So, you’re ALWAYS gonna use your amp as a pedal platform and should mostly be concerned with how good it sounds clean at home volumes. That is, unless you have an insulated music room or unless your house is an isolated barn out in the country. I have a 5W 5F1 and if I “crank it up” at home the police will be at my door in a matter of minutes. Braking up a PRRI at home is a mad proposition for all of us who live in condos. Note also that volume-wise, a 15 watter on ten is not too far from a 30 watter on 10… So the relevant question is rather whether YOU prefer the sound of a small amp pushed a little more, or of a mid-sized amp that’s played pretty low on the dial (say 2-3). I compared PRRIs with DRRIs at conversation levels, and DRRIs with a Vibrolux and my Tremolux, as well as a 15W SCX2 with my Tremolux. Almost every time, to MY ears, the bigger amp sounded better. Very clean, and so in need of pedals to get dirt – but again, that’s the same proposition for a PRRI. Of course, my Tremolux (and your possible Vibrolux) give their best when pushed a bit, and IME it's lucky if between rehearsals and gigs I hit “6” on the dial a couple of times a year. Then it sounds GLORIOUS. But even at very low volume for home use, it sounds fab. I second what others said that a new PRRI is less hassle and less money because a vintage amp needs to be thoroughly checked and serviced. Ideally, you should have a trusted tech, and be able to show him pictures of the amp (including a gut shot) before you buy. But even so, in the longer run, the Vibrolux might be a better value by far. The price you mention is really at the low end of the spectrum, even assuming it’s late ‘70s and not in a perfect state. Whatever you do, you can’t go far wrong and I hope you enjoy your amp!