After the fact, I'm shocked that I could get such good alignment on the Polarie quickly, right out of the box, allowing me to easily achieve 1 minute exposures at 420mm (Canon Rebel T4i with 300mm F4 + 1.4x extender) without star trails. Sitting on a heavy tripod and a Manfrotto 410 geared head, this was terribly unbalanced, however, and the weight of the camera and lens threw off alignment just enough that 1 minute was the absolute limit.
Right out of the box, the Astrotrac is not the least bit close. It is my understanding that it is capable of better accuracy than the Polarie, but only after much tinkering.
Polarie Manual, polar scope illustrated on pg 23
http://www.vixenoptics.com/PDF/POLARIE%20Manual.pdf
Astrotrac Manual
http://www.optcorp.com/pdf/AstroTrac/AstroTrac%20TT320X%20Instruction%20Manual%20v1.0%20-%20Web.pdf
Long story short, once you learn how to adjust it, the Polarie scope is very quick and easy, just adjust for the date and time, line it up with Polaris only, and you're set! The astrotrac scope is illuminated (that's nice) but needs to be modified, collimated (explained here: http://www.fredmiranda.com/Buzz/Collimating%20The%20AstroTrac%20Polar%20Scope.pdf), and then aligned with three stars. After all that, what I don't like is the three-star alignment. Even in less than perfect sky conditions, alignment with just Polaris was still very quick and easy.
The alternative is modifying the arm on the Astrotrac to hold the Polarie scope.
Or possibly just buy the Celestron Advanced VX mount, though I can't spring for the 8in SCT at this particular time, however. What do owners of the AVX mount say?
EDIT: I realize I have been very spoiled by the ease of Polarie scope.
