Your drift will depend on how it is out, it can be in any direction, if you want to find out how bad it is there's a program called, I think pecpro, download it and it will show , or just calibrate in phd the guidescope, then switch off guide pulses but leave your 50 pixel guide box up..... How long til star is out of box, under 30 mins you could do better.
As for solid, this is the plate I have mine setup on, never moves.
http://www.iceinspace.com.au/forum/a...se.php?a=81157