No experience with 910's, but have owned 810's and still have 710's. Great sound from ADS, if price is right go for it. You can always sell them if you do not like them - there is a nice market for vintage ADS.
3 responses Add your response
I've owned most of the larger ADS models. The 910 is a powerful speaker; sounding like a larger, more powerful version of the 710 and 810. Notably deeper, more powerful bass.
Not as refined sounding as the later, larger models such as 1590 or 2030, which use higher spec drivers than the cheaper models (and the 910).
By today's standards, they lack some soundstage and imaging refinement, but at around $500 USD used they are a great value.
The domes are delicate, of course. Parts availability is a long term issue with any vintage gear. There is a guy in Arizona that rebuilds the drivers, so for now they won't become dinosaurs.
I had some and they likes a little bit of power from what I remember. I had and amp from a Yamaha rack system and it broke up bad. I had to replace it. I saw another speaker so incredibly cheap on eBay. Mission made some great stuff in England and they sell for nothing. But I don't see the bigger ones much.