PC and MAC versions capable of AutoCad compatibility

AutoCAD is getting bimmed up(it has to catch up to Archicad - which can now calculate load paths, even point loads on I beams, calculate the temp of the house, spit out a quantities sheet for materials) so AutoCAD will have a 3d script soon. Corelcad $US600 is almost identical to AutoCAD 2006 so file compatability shouldn't be an issue, using DWG, DXF. X7 will open these unless the project is bigger than 20 meters.
As far as Mac's go, users seem to love em and are willing to shell out big bucks for something that looks like it comes from star trek. "Maacks"(that's how you are supposed to say it, like James Bond) on paper seem better, have better advertising, but do you really needy them? I worked at a firm building 20 tonne trailers and used Solidworks, to test their strength $16k software, on a $2k Pc.
Now I might get a lot of mac users saying that they are slimmer, streamlined, cooler running, bug free, outperform a PC - basically give you a mac ad. All true and they do look good in a doctors office, but an engineering office where you are wearing work boots and overalls?