YANQ post (Yet Another Newbie Question)

Ok, I'm looking into 3d printing for a variety of purposes. I am not in a hurry to purchase, (need to wait for tax return next year) So I figured I would do some research into 3d printers well before I buy. The problem is, I don't know enough to really know if I'm even asking the right questions yet. So can anyone link some useful information to read up on? As for the purposes I am looking into 3d printing for: mostly casting use. I plan on lost wax casting smaller pieces. Plastic works fine with lost wax casting, It typically burns out reasonably clean, but I still need to look up which ones cast the best. as well as experimenting with wood filament. (seen enough to know laywood here is the most reliable at least) and printing some small display stands too.

The main questions groups I have right now are:

1. if I am going to be trying to smooth surfaces on my prints, am I correct in assuming that smaller layer thickness is more important than smaller nozzle diameter? If so, how small of layer thickness do I need before I get diminishing returns? 0.05mm? 0.1mm? obviously smaller layers means greater time to print, but what other drawbacks to smaller layers are there?

2. what's the best method to clean up the lines on the side of plastic prints, and how smooth can I really get the sides? What type of plastic cleans up the best? And can the wood filament prints really be cleaned up with sandpaper effectively?

3. the obvious 3d printers questions. I would assume most people looking to get started are looking at the best bang for their buck. I know that $500 is more or less to little to expect good results and a positive experience, so I'm planning on spending more than that. I've seen plenty of printers listed on various sites in the 1-2k range. I *might* be able to swing as much as $1200. any obvious ones I should look into? I've seen a few similar printers in a wide variety of places, and searches on chinese sites like aliexpress etc return large numbers of almost identical printers. (examples of the three most common archetypes I have noticed are ones where the bed is stationary and the printer head moves, both in a delta style and a more normal xyz axis setup.
http://www.aliexpress.com/item/-/2003582069.html

http://www.aliexpress.com/item/Newes...053243381.html

and ones where the bed moves for the z axis. (making me wonder if this has a tendancy to throw off the piece since it's moving)

http://www.aliexpress.com/item/Geeet...052467051.html

None of which are being considered for purchase by me, just noticing that there are large numbers of these types with minor variations. i.e. http://www.aliexpress.com/item/D-for...876150457.html
is a variation on the smaller delta printer.
and http://www.aliexpress.com/item/THREE...218115177.html seems to be a more expensive variation on on the geeetech one.

Are there any obvious advantages with any of those three archetypes? I'm assuming that chinese manufacturers are less than reliable, it's just easiest for me to post quick links that way, since I can show the pictures to try to explain what I mean without needing to know names, and I've used aliexpress a lot for electronics. Still I suspect it's not the best way to go. But curious how the chinese printers and more importantly filaments compare to ones made in america or europe. They bad enough to really run away screaming? (my gut says yes, which is why I'm on this site right now) Assuming that's right, where should I be looking? which manufacturers are really the best for a total newb to get into 3d printing. and what price range should I really be planning on?

1. Yes. Below 50 microns (.05mm) you have diminishing (but still detectable) returns. Only you (or your customer) can dictate what is acceptable and what is not.

2. I don't have suggestions on postprocessing, sorry.

3. If you want precision, you want metal components, linear bearings, and precision ball screws (vs plastic, plywood, drawer slides or threaded rod). A quality printer can be made anywhere in the world, if the manufacturer cares to spend for quality components and uses a well-engineered design. Evaluate your printers based on their output and ease of use, not where they are made.