Well, the Trotec's are at the top of the line on laser quality. I've not seen a better built machine yet. Their Job Control software is very good as well. The 1500 is a monster of a machine. You mention plate glass etching. If that's the plan for the laser, please test it first. Lasers create the illusion of glass etching by creating micro fractures in the glass. So there is no depth to the engraving, and glass is a really unpredictable substrate. You can engraving 2 pieces of glass, side by side, and one will look great and the other one will not. I could write for an hour about our experiences with lasering glass. In the end, if the graphic permits, you're far, far better off, from a quality standpoint to sandblast glass. It actually cuts into the glass and the finish is superior to the laser. It's also extremely consistent across glass. With lasering, you'll get tiny shards of glass that flake off in your hand.
I've seen people on forums say how they do a lot of glass on the laser and how great it works and then they post examples and it makes me cringe because the quality is below standard.
You can't cut PVC at all, or anything with PVC in it, like vinyl. What it does fantastic is cut acrylic, acrylic letters, etc. If you do a lot of gift type things, you could line them up and engrave a lot at one time, so that might be a good thing for you. We have found them to be exceptional additions to the sign business.
If you have any questions moving forward, I'm happy to help. Just PM me and I'll send you my phone number.