Review on Superior Performance and Versatility: Grandstream GS-GXP2135 Enterprise IP Phone with Gigabit Speed and 8 Lines VoIP Support by Kristen Lopez

We've just deployed over 50 of this model where I work. I'd say this is a very good, if not great, everyday business SIP phone. Especially in this price range. You get a beautiful color LCD screen and four pages of BLF function keys. The phone is also quite attractive and looks quite professional despite the price. However, it has a few features: 1. The built-in non-standard ringtones are absolutely terrible and don't match the volume. So if you have the ringer volume set to the level you want to hear the ringer at by default, a call comes in that is configured to use a different ringer based on the CID or alarm information, the ringer is deafening. Who put these tunes together? 2. So I had to find a decent custom ringtone online to replace one of the built-in ones. The process of getting them over the phone is time consuming and overly complicated. You can't just download it from the web interface. No, you need to convert the WAV to their own format using Grandstream's proprietary software, then put that file on an HTTP or FTP server, and then configure each phone to know what to look for there. It's fine for bulk deployments if you set it up in a deployment template, but I'm surprised there isn't an easy upload feature when you only have a few phones that need their own ringtone.3. You cannot use the phone book to select someone when transferring a call. You must use the BLF button or dial an extension. I don't get it at all, it seems like a pretty easy feature to implement.4. Apparently I've found a new bug that Grandstream didn't know about. If you change the 4th VPK to something other than the default, almost all the buttons will stop working unless you change the call screen to "Account Mode" in "VPK Settings" -> "Call Screen Settings" in the web interface. It looks like they are working on a solution but this workaround is the solution.5. The screen is not high res, so long caller IDs will be truncated unless you click the Hide Labels button. Overall this is a very good phone. Every SIP phone has some features, this one might be a little more confusing than most, but this thing just doesn't get any better in terms of features and price. It works well and our users seem very happy with it! For example, if we had chosen Yealink phones our cost would have been more than double and I doubt I would have been approved for the PBX upgrade project. If you're looking for budget phones that basically perform like phones twice the price, you really can't go wrong with the GXP21xx series.