I understand. I believe Grandstream has greatly improved their products in recent years. They are pumping out new firmware for phones and ata's very frequently. But hey, I still have an unlocked Linksys PAP2T that my fax is connected to. The things just keep working.
I've used the Grandstream HT-802's in remote situations because I can remotely update and change them using Grandstream's free GDMS software in the cloud. Their devices (unless blocked by local firewalls) are always available to the cloud administration. I have heard of people finding the HT-814's to be too difficult but if you use the GDMS cloud, its pretty straight forward.
So there are pros and cons. Sometimes, its worth $50 to bury the hatchet and try something to see if they will now meet your needs. Get it from Amazon and if you still think it sucks, return it.