I've been looking at various CNC's that are relatively small and portable.

Shark 2x4 (Rockler)
Powermatic 2x4
Avid 2x4 and 4x4
Camaster 2x4 Stinger I and II

In general: There are so many options, features, and addons its hard determine what might be the best general purpose unit. I'd like to get something I don't have to upgrade in a year.

Purpose: I plan to cut out templates, do some engraving, cut out small parts, possibly cut mortises. I was thinking if I had a 4x4 machine, I could take 4x8 sheet goods, cut them in half, and work on 4x4 sheets. I'll be working on furniture mostly. It seems like for working on hardwood, 2x4 is enough for most work?

Size and portability: I was looking at the Stinger 1 as it looks like it might be easier to store it vertically when not in use? Has anyone done this? The stinger II looks nice but no portability really. Is anyone using a CNC on casters or storing it vertically?

Options: Should I be focused on units with water cooled spindles or routers? Are there any key features I should be looking at , like travel on certain axis or a certain number of axis's? It seems like the Camaster is a pretty complete system.

Thanks for any help.