As far as I can tell by reading about the LX90 versus the LX200 GPS, the GPS version allows you to automatically find Polaris and true north, versus having to find true North manually with the LX90. Once you find Polaris with either telescope, you still have to perform an alignment on 1,2 or 3 stars depending on what you select from the Autostar menu, so is the GPS really giving you that much more capabilities for the extra money (e.g. $800 difference for the 8 inch model. It seems that unless the GPS version allows for much easier alignment of the alignment stars (or other capabilities I am not aware of), the GPS really does not do much for you beyond finding true North, which really is not hard, and should not require having to pay almost $1000 for it.
The LX90 has over 100,000 objects in the GO TO data base versus about 30,000 for the LX90, so you get extra objects, but if you buy astronomical software (i.e. The Sky from Software Bisque and a serial cable for about $130), you can have over a million objects for use with the LX90. The LX90 can be used for digital photography and has computer port control, so there is no difference in this regard between the 2 telescopes. I did read what seemed to indicate that the tracking capabilities of the LX200 are more advanced, but for the beginner user, will this really make a noticeable differnce? Probably not.
I recently went through this exercise and decided that the extra money for the LX200 was not worth it for me, given that the optics were the same, and the GO TO capabilities were basically the same once you find true North. So I bought the LX90 10 days ago, and am now very happy with it. I must confess, that being a beginner, I did struggle for a few days until I learned how to properly align the scope, but once it is correctly aligned, it works great in finding objects, and keeping them tracked in the eye piece. It also seems that I have improved the performance of the LX90 by either calling the nearby airport to obtain the latitude and longitude of where I am to help in the setup process, or by punching in the exact longitude and latitude of where I am by checking the GPS in our Honda Mini-Van. Is this cheating? I don't think so.
Regarding the weight of the 8" LX90, the scope weighs 30 lbs, and the tripod weighs 20 lbs. For me, this is at the extreme of my comfort level. It is heavy when you carry both pieces (50 lbs)together, but one person can do it. The 10" would be great, but knowing its greater weight, makes me feel that I made the right choice for now by selecting the 8" LX90.
I would like to hear others opinions and experiences.