I know most of us
realize that the 10" will show lots more than a 4" refractor, but the 10"
XT10 weighs a LOT more than my 4" refractor too, and takes longer to cool
down. I can pick up my 4" refractor, mount and all, and bring it outdoors on
a moment's notice. There is always that portability vs. aperture thing in
amateur astronomy .....

Put wheels on the dob. Instead of portability vs aperture, think portable
aperture.

For
planets, star clusters, doubles, and extended deep sky objects, a nice, 5"
instrument will do a nice job.

Truth!

One caveat is that Maks and SCTs take awhile
to cool down, especially if you bring them to the cold outside from a warm
inside. Best if you can keep those type of scopes in an unheated garage or
shed, so you can cut down the cooling time.

Truth! And this also applies to dobsonians. Then add active cooling.


john