Hello again rogerfries, somewhat as KSellon eluded to, if you can afford to go with the bigger machine it is always nice to have more than enough power instead of not enough. To answer your other question, these machines will do a really nice job on the thinner materials as well. That is part of why I included the information on the different nozzle sizes, they will help to tailor the cut to give you the best cut quality and their applications are typically dependent on material thickness, typically the larger the diameter of the orifice the thicker the material that they are designed to cut, in some cases they also suggest different air pressure settings to match a particular tip. There may also be a scarfing tip combination available for these machines(these are consumables that are used in place of the regular nozzle/tip set-up), this is a system that can be used to gouge out old welds, remove material to repair cracks, or simply prepare weld seams to allow for more complete penetration. Good luck and best regards, aevald