@Speedling someone?..ouch, then again I was under a different username when I sent you that (ten75k)....have you used it yet?
@steined I have a running thread on things I've made
https://jetboaters.net/threads/3d-printed-parts.605/#post-6591
I'll comment on plastics vs metal base on the Makerbot starting point.
your options out there are becoming limitless fast. It all comes down to cost vs quality of course. Top of the food chain is SLA parts..big money awesome outcome. down from that come your laser based or liquid printers, then you head into the FDM area (fused deposition material), which is the most common and easiest.(makerbot is FDM, basically melts a plastic line and places it/cools quickly)
In the FDM arena it comes down to strength and the "overhead" to support speed and complexity. Most FDM machines use an ABS plastic, easy, affordable but offers little in the strength department. Polycarbonates are stronger, we are just now looking into getting one of these. In the link above those parts are built at a .007 resolution with ABS, "ok" for flat surfaces, the blender cover is sloped so you can see the steps in it.
Makerbot: I know a few people that own them and like them very much. The one you are looking at has a a 9x6 plate. That is excellent, X/Y will be used more than Z in almost every application. 100 microns is excellent (.0039) about 2x better than what I'm showing in that link. for conumer products You are definitely in the right area, and the prices are dropping fast. 3d systems now competes in this space....I don't know what your end product will be, this will probably do most everything you want, just keep strength in mind.
I believe these type machines print straight to the part. Meaning it does not utilize support material, its easier to manage but would slow things down. Support material is a lesser plastic used to support features in a print like overhangs or hollows so the machine can print more above it. We need to bathe our prints in a LYE solution to dissolve the support material. no big deal but a pain to maintain the tank and takes couple hours.
you have a design tool? ProE, solidworks? etc?. sites like Grabcad allow you to download and modify files. typical file export is STL. Use of these printers are easier than you can imagine....the software is self-aware
In other news: my company is about to buy a 3d handheld scanner !! I'm going to scan my families heads and make a chess set !! and bobble-heads !!. I saw a family Foosball table recently...awesome !!
good luck......you wont be sorry, the things are wicked cool !! and a great exposure to kids for creativity