Well they all look VERY big to me... and how do you set them up on a rough
surface...

As others have pointed out, inch for inch, a Dobsonian is more compact and less
cumbersome than an EQ mount.

There are several vendors in Canada that sell scopes similar to the Orion and
Hardin Optical line and seem to offer good prices. No need to pay the US duty.

When it comes to optics, well, it is nice to get by without spending a great
deal of money. The problem is that decent quality optics are expensive to make
so if one is buying a 6 inch scope for $200, it means that some corners must
have been cut. The two places where serious compromises are normally made is
in the optics and the mount. A poor scope on a shaky mount is just not fun to
use.

On the other hand, many of us here started with a poor scope on a poor mount, I
certainly did. It did not stop me from enjoying astronomy. But I soon moved
up.

So the hope I have is that you can spend your money on a scope that is capable
of providing many hours of enjoyment with out learning the hard way.....

That said, if you are determined to buy one of the two scope, the 90mm or the 6
inch, I would have to suggest the 6 inch and make sure you keep all the
packaging so that you can return it if you are dissatisfied.

jon