You might want to consider
Obivoice.com. I had Callcentric and GV for a while (Callcentric for e911 and CID/CNAM, and GV for calling). However, I also experienced spotty CNAM and degrading call quality from GV. I decided to head the "No more XMPP for GV" off at the pass and subscribe to a cheap pay service.
I ported my GV number to CallCallcentric with a "Pay per use" plan, and the quality is significantly better. CNAM seems better too.
However, the very next day, I stumbled upon
Obivoice.com. I signed up for a free 30 day / 60 minute trial, and am very impressed. The UI isn't as polished as CallCentric, and there aren't as many options, but here's teh biggest reason I'm more than likely going to port my number away from CC and go to Obivoice - for unlimited incoming, outgoing, voicemail, e911, CNAM, CID, and a few other things, if you sign up for 2 years, its a whopping $59.99 TOTAL. Yup - $2.49/month.
Check them out, sign up for a free trial and compare. In my case, the quality for both CC and Obivoice is noticeably better than when I had GV in the loop, so both are good options for me. But Obivoice is winning because of the price (and I don't really need the advanced features of CC).
By the end of the month, I may well be a paying Obivoice customer.
