I'm sure it is too much to expect since Vox only recently redesigned the Valvetronix amps, but it would be nice to have a bi-directional USB feature on them that allows you to playback your tracks while playing your guitar and recording/jamming using the amps speaker. It seems like this makes a lot of sense and should have been taken into account in the design and manufacture of the plus series. I wonder if the pro plus has it. The Valvetronix amps have a lot of good things going for them.

With the addition of an interface pedal like the Digitech RP350 or its newer equivalent (RP355?), I guess you could get the bi-directional functionality; but then you could use any amp to direct the speaker output to, you wouldn't need a USB amp. The same would be true for the Zoom pedal I guess. My RP350 does a good job of it.

Something that would be nice would be a recording pedal with a huge capacity for using big external memory cards, similar to the capability of the JamMan looper pedals; or something with even more memory. It could be popular and not much more expensive than the JamMan looper. This option would be more portable and allow you to bring a lot to the gig without having to have a laptop or desktop at the gig.