After some time trialing printing on acrylic I've decided there is no real advantage over glass with kapton tape. Although it works, it doesn't offer a strong enough adhesion for larger parts. It also suffers from warping as the heated plate warms up. So its back to kapton on glass for me. Incidentally I have had a batch of kapton tape specially cut to 140mm, to suit the UP printer. This has made the job of replacing damaged tape much easier. Previously I had to carefully line up multiple strips.