The phone itself looks great on the desk and has all the features I could ask for. Being a SIP newbie it did take me a while to get everything set up but I was also learning the ins and outs of VOIP as well as setting up a PBX at the same time. I'm using PBX in a flash and now everything is set up it has been rock solid for a week or so.
The one minor issue I've had is although you can reprogram the "pre-programmed" keys (Messaging, Rec, DND, transfer, conference and consultation) These can only be programmed as DTMF. In contrast the programmable line keys also support BLF (Busy lamp feed). What this means in practice is I can set up the Do not disturb button to dial *76 to toggle DND at the PBX but the lamp on the phone key does not follow state. Programming the same *76 on one of the fully programmable keys toggles DND at the PBX and the lamp also reflects the state correctly. I've emailed Gigaset support to see if there is any way around this as it could be an oversight on my part. If not I'm hoping a firmware update could resolve this at some time in the future.
Overall I'm extremely happy with the product and will soon be adding a DE700 and some DECT phones from Gigaset.