Panasonic UK have sent me a DMP-BD10 for review, which came to me as v1.0. I upgraded it to v1.4 - and now it has CUE when playing BD movies. I'm sure it didn't before - it was instantly noticeable on the red Fox "WARNING" screen at the beginning of the Fantastic 4 disc.
unlike the DVI and stability issues gained by upgrading the Toshibas.
Weird - I never had any stability problems from upgrading my own HD-A1, that's the first I've heard of it...