comments on optical tubes?

I am looking for a nice optical tube assembly for a custom machined mount (100lb capacity). I am presently doing film photography, but want to go to ccd in the near future. I had been using a lx200 classic 10" f/10. So am considering a meade (gps)newer 10" f10 or f6.3 optical tube with mirror lock. Also the meade lxd55 10" f4 schmidt-newtonian looks interesting.
So any comments on how well the newer gps optical tube stops mirror shift? Also any comments on optical quality for photography with lxd55? Any other reasonably priced tubes in 10"-12" range, someone has had success with?
Anthony

I own a 10" LXD55 UHTC. The optics are ok, just don't expect $4,000 performance from an OTA worth about $550. Also, for ccd work, the standard, mostly plastic focuser will have to go. So, plan on spending some extra bucks for that.