Here is a PDF flyer I like to show people when you compare a cheap front loader to a more expensive one... 
- Hinge. Look at the door hinge. This door is going to be opened and closed thousands of times during the lifetime of the machine. The weight of the door has to be supported by that hinge. 
- Suspension. You can't see it, but the PDF makes this point very apparent. 
- Tub. Stainless steel doesn't hold odors. It doesn't grow mold. The looks of all front loaders are deceiving because they always use stainless steel inner tubs. The outer tub is something you don't see. These plastic tubs are the reason why front loaders get stinky after a while and need Affresh. Teardowns of used front loaders show the inside of the plastic tub as being absolutely filthy. The worst part, they contain ridges inside to strengthen the plastic, but instead trap dirt. 
- Trunnion Shaft. A larger trunnion shaft means a larger bearing. Bearing failure is a big part of the problems that front loaders have. Lots of people tend to overload their front loaders. The big problem is, North American front loaders have large tubs to attract consumers, however the machine isn't equipped to be able to handle the weight of the wet clothing that sized drum will hold! (Hence, most consumer grade front loaders lasting between 5-10 years, if that.) 
- Steel parts as opposed to plastic parts. Which would you rather have? The only rationale for using plastic parts is to bring down manufacturing and labor costs. 
- Baffles - Plastic hollow baffles hold dirt, smutz, mold, etc. European front loaders use metal baffles for a reason, you shouldn't consider anything else. 
That's a few of the key differences right there. 
http://home.huebsch.com/adv_pdf/aa07-502.pdf