I built a Rostock MAX V2 as my first printer and learned a bunch from it, but I was constantly tinkering with it and never got it to the oint of “point and shoot” although I got many acceptable prints. After that I bought a Powerspec 3D Pro 2 from Microcenter ( http://www.microcenter.com/product/486803/3D_Pro_2_Printer?ob=1 ) . The build volume isn’t huge, but it does good solid prints and fairly fast. In all honesty though once I went CNC I kinda quit playing with my printers. The Rostock is on semi-permanent loan to a friend of mine, and the Powerspec is in my office, but hasn’t even been plugged in since I moved almost a year ago. As far as single/double extruders goes, figure out if you really need them or if you are buying a machine that can be upgraded later. They can be a real pain, and 95% of the time I never use mine(but maybe you have a specific use, that’s up to you). You might consider getting one of the cheap Folgertec Prusa kits and building your own. You’ll likely see different features later on and by that time you’ll want a bigger better machine and you’ll have gained a ton of experience for very little money.
As a side note, last year my company asked me to research getting a new 3D printer for our prototyping shop. They wanted to go “BIG”, so I found them this and they bought it. So if you think you might need to 3D print full sized furniture and have money stashed away for a new car, it might be worth considering, haha!
I’ve gotten to play with it quite a bit, it is a nice machine!