I've had a Toneport UX2 for about a month now, it's pretty good value for money. The only downside is the real-time monitoring, to avoid latency I use a separate small hi-fi plugged into the toneport's audio output with my recording software ( in my case Tracktion ) outputting to another set of monitors. It has a good set of amp simulations, effects and such, but you can also run it 'clean' and use other post processing if you wish.

The other problem I had was the latest drivers from Line6 were flaky on my PC, I stayed with the drivers out of the box and it's fine. If you don't need phantom power for a microphone, the UX1 is a bit cheaper and does the same job.