I have a Thermo Dynamics Cutmaster 38. It cuts everything I have ever asked it to cut, including a part of a semi truck frame. 30 amps, 110 or 220 auto-sensing, and the comsumables are reasonably priced. Also - do yourself a favor and buy 2 of the "toilet paper" air filters, run them inline from your shop air to the plasma cutter (I mounted mine on the back of the plasma/welding cart). With super dry air, the tips and electrodes last forever.
Good luck on your purchase!