Equipment Help Needed

Guys, I know I have been brewing long enough yet still ask some stupid questions... But on the side of equipment, my system is very simple. By that I mean it consist of the following:
- 1 Banjo Burner
- 1 Cooler for a Mash Tun
- A Saw Horse to hold the mash tun
- 1 Keggle

So I am thinking of upgrading and see ads on Craigslist like the one below, and am wondering if it really does make things easier. Or if it would be better to find a linear stand similar to the one Sam Caligone uses as his test batch system.

http://atlanta.craigslist.org/atl/for/2044509562.html (Craigslist)
http://www.brew-magic.com/bm_samtest.html (Dogfish Head)

But I am also looking at getting another keg (legally) to use for a mash tun. The thought being that I could just heat my water in the vessel, and add the grain to mash. Does anyone know how much temperature loss you can expect when swapping from the insulated cooler to the keg?

I built a single tier system with a pump. I didn't want to have to carry stuff up and down a ladder (especially drinking). However, I built the stand too high and wound up having to shorten it. It's strictly a matter of space/taste. As far as the temp loss, I heat my mash water to 10degF over my mash temp and dough in. the temp falls 10 degrees and stays rock steady for an hour with no insulation. Remember though, my keg is preheated by recircing the mash water. - Dwain