Servicable economy class phone
First, this phone is typical of IP phones in the sub 100 economy category. In other words, you are only out around 20 more for one of these, than you would be for acquiring an ATA, like the Linksys PAP-2 Linksys Internet Phone Adapter with 2 Ports for Voice-over-IP PAP2T-NA - VoIP phone adapter or the Grandstream HandyTone 486 ATA or even the very basic ip phone...
I have had two of these phones in service for over a year now, and I am about to purchase one of the 6 line versions (the 2020) which is a little more (around 135) but a bit nicer. The phones have worked without any problems, and were fairly straightforward to configure, both on a direct to provider connection to two of the major SIP providers, and to an Asterisk (PIAF PBX in a Flash) server.
On the down side, the phones have a slightly marginal aesthetic to them, the keys in particular, and inbound audio suffers from low volume. Outbound audio has a definite clipped sound and slightly narrow audio bandwidth.
But, this is a very inexpensive phone - not much more than an old fashioned analog phone at your local big box discounter. If you want better quality, spend 200-400 and get yourself a Polycom, Aastra, or Cisco. If you you are a CAREFUL shopper on a budget, this phone could be a good buy. If you aren't a CAREFUL shopper, move on.