As for the 80ED. I have heard good things, but I have also heard about
collimation
problems, and trickyness in collimating. Is this a concern that should
steer me away
from this scope? Any experience with it? -Thanks, Tom

The only thing I have experience with it the Orion 80ED.

When I bought mine, I bought it from a local telescope store. I've done
business with them for 20 years so they allowed me
to check the collimation of the 7 ED's they had in stock, so that I could
pick the best one.................................... they were
all pretty much dead on. I've only read one comment in the last year or so
about someone that had a slight collimation problem
and he unscrewed the 3 screws that hold the focusing assembly onto the back
of the OT. Apparently he was able to achieve
perfect collimation by tweaking the assembly and then tightening the 3
screws back in place.

My 2 cents,

Francis Marion