I currently own Montis powered by Pass Labs INT-150 I agree with the comments that they do sound best with classical/jazz/acoustic. However in my listening room they are more than adequate for rock at any reasonable volume. If you are an extreme bass freak, they probably won't cut it for you. As far as bass to panel integration, in my opinion the models with powered woofer with DSP are where ML finally got it right. Maybe not absolute perfection, but very, very close. Anyway on to your specific question about Vistas. These were the entry level with the narrower 9" panel and 8" bass reflex. Similar to the Theos when I was looking. I found the bass to be not adequate at all on that model. For me at least a subwoofer would have been a must have.
Martin Logan speakers
Are Martin Logan speakers still considered to be high quality speakers? (I have an opportunity to buy a used pair of Vistas) I have an old Audio Research VT130 amplifier. Would it be a good fit with the Martin Logans? If not, what would be better, but not outrageously expensive?