How distortion-y? Well, with the lower rails and 6088 tubes, we're talking 1.5-2% THD at 1V RMS out. Yeah, that's huge. Sonically, it actually isn't that bad. I could see lots of people liking it. But we are getting well above the threshold of audibility here.
I don't really care about distortion as long as it sounds good. I say keep the 6088s!