Want to practice guitar, vocals or other instrument to backing tracks without having to be connected to a computer? That's why I got the V-Studio 100 and that's exactly what it does for me. It is a very well made device, typical Roland quality and works as advertised.
It has a nice six input mixer, an SD card recorder and a DAW interface section that works when connected to a computer via USB. The box comes with SONAR VS, and NI's Guitar Rig 3.
Although I can't find any "properties" data on the Guitar Rig 3 program I'm pretty sure it's a 32-bit version which would explain why it will not work as a VST in SONAR VS while running on my 64-bit laptop. That's pretty frustrating, however, the GR3 works just fine with the VS-100 while running as a stand-alone app. That's too bad.
I also had to download a 64-bit Windows 7 driver for the VS-100. The one in the box wouldn't work with my machine...Vista or XP only. A quick Goog search found what I needed on the RolandUS website and the downloaded driver works perfectly.
The VS-100 sound is very good, for a product in this price range and the interface is pretty easy to get used to and use. You can also play a .WAV backing track from an SD card and record what you play along with it. That's nice. The unit accepts SDHC cards as its storage medium and I think it can take up to 16 GB although the documentation doesn't say. I know it works with 8GB for sure.
For me this was a good purchase, well worth the money to get some much needed mobility. It's nice not to have to light off the whole studio just to practice with a backing track and it's nice to be able to do that and include a few of friends just about anywhere you've got a wall plug.