Hoss,
I followed your link to MakerFarm for the kits. Looks like a good find. Do you feel that I would be thinking correctly that if I got their 6 or 8" prusa i3 kit Prusa 6" i3 Kit - Kits that if I wanted to make a larger (and not wood framed) machine later I would basically just need to replace the rods and belt to fit whatever frame I came up with? i.e ramps, lcd, steppers hot end and extruder would all be reusable. Versus for example the Printrbot simple which appears that it wouldn't be upgrade-able without buying more steppers and maybe replacing the electronics.
Having completed your G0704 cnc mod I feel fairly comfortable with assembling a machine, but from the research I have done, it seems like MakerFarm's kit would be pretty tough to beat compared with finding and buying all the parts at 4-6 different vendors.