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Plasma CNC for Sign Making 
Go to www.FourhillsDesigns.com. (my commercial steel and glass site) All of that art, most of it decorative signage, starts out with CorelDraw CDR files, gets processed by our DXFTool and imported into SheetCAM. Same basic files can be used for plasma or router but the CAM process is different. Plasma is not as simple as just putting a shape file on the table and making a cut. There are a lot of variables in plasma you don't have in routing. Pierce height, pierce delay, cut height, lead-ins/outs, kerf offset, clean compressed air, correct tip, correct cut gap, etc. Unlike wood or plastic, Metal moves up and down (sometimes a LOT) as it's heated from the cutting process. From experience I can tell you that trying to do decorative cutting with a plasma that does not have Automatic Torch Height Control is a frustrating and expensive process. You will go through consummables like they are free (they aren't).
The Torchmate system uses proprietary hardware (Flashcut) which only works with their control software. You will need to buy their THC solution.
We also have the vinyl cutters, wood router and desktop engraver and there is a market for shops that can do all of the aspects of signs and decorative accessories.
Don't let someone sell you something that won't work with Corel (i.e BobCAD) or some nesting solution. You don't need either.
If your intent is to have mulituse table, you need to buy for both purposes. The table needs good speed and acceleration for plasma. Ususally plasma gantry's are lighter and not as rigid because it's non-contact cutting with no cutting forces. For routing of wood, plastics and light aluminum you need a bigger gantry to carry the added spindle weight and to handle the cutting forces involved. That means you would normally gear the table differently and trade high speed for more torque to move the heavier gantry.
Typical plasma cuts are done from 80 to 280 IPM. Wood and plastic is cut (with conventional routers) at 15 to 60 IPM. Signfoam is cut at higher rates but you need better accuracy.
With a combo table you need both speed with acceleration AND torque and precision with a heavy gantry. Also understand that plasma cutting is a VERY nasty, smokey and messy process and you need things like a water table and/or heavy downdraft dust extraction system, where as routers need more focused dust extraction close to the cutter. If you are in the same building as your business the plasma needs to have it's own sealed room.
I don't like any direct coupled rack and pinion drive system. Without some form of gear or belt reduction, you have speeds you can't use and a lack of torque you do need. Most rack & pinion has about a 3:1 speed increase with a corresponding torque decrease and the resoltuion (smallest incremental distance you can move the machine) is low. Since most steppers can spin 600 to 700 RPM when driven properly and 3:1 step up results in potential rapids of 2100 IPM......way too fast for most machines. So all the speed you can't use (anything over about 400 to 500 IPM) is just wasted. Some just oversize the motors like crazy and call it good. Consider also your resolution is at something like .0152. Microstepping can help with resolution but cannot be counted on for accuracy (totally different thing than raw resolution). A 4:1 belt reduction can result in 4X the torque, 4X the resolution and 1/4 the speeds.
Do some research. You are welcome to join my CandCNCSupport Yahoo group and there are free decorative CDR's there in the files section. You can get a free 30day trial of our DXFTool for CorelDraw and a free demo of SheetCAM. Understand the technical aspects of plasma cutting BEFORE you write a check.
Tom Caudle
www.CandCNC.com
