I have a delta-style printer and it is excellent. Unfortunately my printer is not yet available in the US - I got mine because I joined an early adopter program. Here is the web page for my printer: http://www.atom3dp.com/en/atom2/#top

Delta's have some distinct advantages over Cartesian designs: (1) generally faster printing because they typically have lighter printheads (less moving mass); (2) larger print volume, particularly in the vertical dimension, (3) simpler control electronics becuase there are only 4 limit switches, (4) require less desk space, and (5) they are incredibly cool to watch while printing.

I agree that many delta printer designs are insufficiently robust, which is why I chose the Atom2. It is very well constructed and quite sturdy. The Atom2 also does truly automatic bed leveling which I think any printer should do.

It is true that a delta printer's firmware is more complex than that of a Cartesian design; with a delta there really are no X, Y, and Z dimensions - even though that's what they are called. The printer firmware makes all the necessary calculations to generate proper 3D moves for the printhead, and I have never had a single problem with this.