Here's what I have,
http://www.millerwelds.com/products/plasma/spectrum_625/
Cuts steel and aluminum like a laser knife....it is the bomb....
If you can cut with a torch,,plasma cutters are a piece of cake.
It takes a pretty steady hand to cut stuff freehand,,making a few simple templates really help.
Use a straight edge ( even an old wooden 2x4 will work because it cuts so fast the steel barely gets hot) and you can make a perfectly straight cut,,no jagged cuts,,no slag to grind down.
One thing a plasma cutter will not do is make a cut where there is a space between the tip and the cutting surface ( say like,, a shock bracket in a tight space )
where a torch would still cut if you were 1/2 inch away from the steel,,
a plasma cutter must be very close to the surface ( 1/8 " ) because it is basically sustaining the arc from the tip to the surface....you pull back too far and you loose the arc and cutting stops. they are great for fab work,,,
but not as good as a torch for " demolition " work....
As far as maintenance,,keep it fed with good dry air,,, keep the tip clean...go for the 220 volt model....