Hi Chris,
There are benefits and drawbacks to the "open tube" design. I think as Andy mentioned portability is the main benefit, but you may need a light shroud to stop stray light coming into the light path. If you don’t think that you require the tube to be shorter for transport you can always consider the solid tube version of this telescope by Orion: http://www.telescope.com/Telescopes/...0/p/102019.uts. It sells in Australia through Sirius optics
http://www.sirius-optics.com.au/orion%20dobs.htm,
and others, and it doesn’t cost that much more.
Cheers.