I haven't checked the drift for a while as I have a pier setup which was dialed in at first use over several nights. I was going to check it again, however, I dont have a reticle eyepiece. What I normally do is use a barlow with a 9.7mm eyepiece and focus the star till it is just inside the eyepiece edges and use that to see where the drift is going. I also have an illuminated polar scope which has markings in it and they are very near to spot on. Also, I can put a star in the camera image plane and watch it on the screen of my pc. Drift is very , very slow, if at all and I sometimes wonder why I guide for shorter exposures. But I will check it. Can someone leave a link for the 127 APO, what is its colour correction like?(Im a lover of natural colour, I prefer reflectors and know very little about refractors). Keep 'em coming, I need to nail this. Thanks.