I'm considering the Celestron Omni 150 XLT (150mm F/5 reflector). I'm principally concerned about overall optical and mechanical quality of the OTA. I'm familiar enough with the EQ-3 class of mounts, and I like the new, improved CG-4, but have no curiosity about it. In particular, how well does the Omni hold collimation? This is a "large" grab 'n go option, so relatively good mechanics are, for me, a must. What are your experiences? StarBlast 6 owners' opinions are welcome, especially anyone familiar with both. Really like the 2" focuser option on the Omni, but the collimation mechanics of the two should be awfully similar.