If you can imagine it (or draw it) and it's less that 6" in any direction, the printer can make it. The limitation within that 6" is that it can't make any feature less the 350 microns (.35mm) in the X or Y axis since that's the width of the bead that comes out of the print head. It has more flexibility with the Z axis having the option for a 100 or 300 micron resolution. The Z axis is controlled entirely by bed height so it can support higher resolution than the print head.
One thing the printer has a hard time with is gaps in the Z axis where you ask the printer to lay down plastic with nothing underneath. You either have to design the part so the printer is always adding plastic to a filled area underneath or add support material to be cut away after the part is printed out. That's one limitation that SLS does not have. It can make empty spaces in the Z axis with no issue. Of course, SLS machines start around $20k.
ABS should be fine for an enclosure if you are not concerned with high heat tolerance. The only thing I don't like about ABS is it starts getting pretty soft around 150C. It actually flows out the print head at 195C. The nylon GF used for SLS doesn't soften up until about 250C. Other than that, ABS is a pretty good plastic, fairly rigid, good impact tolerance, high solvent tolerance.
Keep in mind, you're not going to get parts right off the bed that look like they came out of a mold. However, after some finish work, they can look just as good.