The approximately $90 Sipura spa-841 is a very nice step up from the approximately $65 Grandstream "BudgeTone-101". For the extra $25 you get a much higher resolution display that is capable of displaying alphanumerics. That gives you a display that can see the "name and number" of someone calling you (unlike the Granstream that only gives you the number).
In most respects, this phone appears to be a typical Sipura ATA, with the normal rather flavorful half dozen setup menus. In theory you can connect to 2-4 different service providers (depending if you pay the extra $30) to make it a "4-line" phone or just leave it at the base "2-line" version. I'm not quite sure why they think anyone would pay extra money to turn on extra software features like this, but only time will tell.
Folks that liked their Grandstreams, but hated the fact hat they had no alphanumeric display to display the callers name will love this phone. It displays the incoming ascii name, number and calling time with no problem. In theory this phone also does SRTP, secure RTP with encrypted packets. No telling if this works because Sipura seems not to want to document how to generate or load secure keys.
The bad parts: The rubber buttons and/or the plastic case aren't smoothed correctly and the buttons will stick for the first couple of dozen pressings. They obviously didn't spend much time testing the moulds. The ethernet rj45 is also made with little precision. A normal rj45 cable plugged into the phone didn't work at all. The stock (rather short) Sipura rj45 100baset cable did. I suspect that the phone's rj45 just had weak/defective spring wires and it needed a slightly oversize rj45 to make a connection. This isn't a great sign for their quality control dept., but at this point I'm still willing to take a sipura phone with a crappy rj45 over a grandstream phone with a non-functional message button (like the bt-101 with the latest "stable" firmware).
-wolfgang