This is a very interesting idea. As far as I can tell acetone smoothing does essentially the same thing to ABS, but it’s much more of a hassle and (for me at least) must be set up on a per-part basis. Having a seamless device that accomplishes the same effect with minimal effort could be huge. I’m unfortunately not going to back it due to lack of funds, but if it can prove itself in the field I imagine I’d probably purchase one sometime in the future.
As for your question about whether or not I dislike the rough finish: it depends. For me it’s much more about having multiple options rather than just picking either “smooth” or “rough”. When I do a 0.3mm structural print for my next RepRap, more than likely I just want it done as soon as I can, so I really couldn’t care less that the surfaces appear in quite distinct layers and wouldn’t go through the effort to smooth it. On the other hand, if I’m making a purely cosmetic piece I’d love a polished look.