I think you'll really like them! Their (the company) responsiveness has not been all that great, but adding independent suppliers seems to be helping push things along. The Avalons themselves are bulletproof... currently have 9 of them. I'm running 3 in Canada along with 2 AntMiners. The AntMiner S9 already has one partially burnt-out board, and my lucky S7 (found 2 blocks over the last year, and I bought it used!) unfortunately likes to randomly drop out for no reason on occasion. The three Avalons there run 24/7 at 7.6-7.7 TH stable. The other six I have here in-house. Of those, three have been running for the last 9 months almost flawlessly. Just make sure your controller and miners are running the latest firmware.

Side note... I also run the in-house ones at a slightly lower power setting to reduce fan noise and keep things stable with a slightly bizarre 10" duct heat removal system:

And they still push 7.7 TH reliably, at about 1200W at the wall, 240V circuit. I don't necessarily recommend that second setting as Canaan targets the chips to 90C, but it works well for me...