I use a 4003 Rickenbacker and Fender fretless Jazzbass, very distant in sound, but the sound is very good. Do you wait still not at a studio quality. There are two modes: normal and FX. The fx position does not suit the game with a low (less than Lemmy Kilmister or play in a band of Heavy metal thrash grindcore), the distortion obtained being quite unpleasant. As against this effect works well with a guitar (tried with a Stratocaster), we get a sound from overdrive to distortion. The lack of reverb is a little smell, but it is very acceptable for a rock-blues use (better yet buy a Amplug dedicated to the guitar, if you do not play bass).
I would advise to use a closed helmet, because the mp3 walkman-style open models are not suitable (I use an AKG K 44 cheap and not tiring for the ears) but it is a matter of taste, although helmets "open" generally have a bandwidth limited and too dynamic for that specific use. Two small batteries are supplied with the machine and it fits all jack outputs (on the edge, face or oblique kind Strat). It is prudent also to properly secure the wire helmet with low strap if the contact of the jack would tend to spitting. There is also an auxiliary input stereo mini-jack for an MP3, for example.
In short, this little thing is perfect for those who do not go on holiday with roadies, or for mom with beautiful weekend story to benefit from the effect of "diversion".
Vox Populi, Vox déi.