Questionable Product

We purchased this dryer along with its matching washing machine from the local sears store. Our washer had gave up the ghost (dryer was still functioning) and so opted to replace them both at the same time. The washing machine in the set works great! The dryer however, whole different ball game. When it is working it does a great job. The problem is at about week 5 the thing quit working. Had a tech come by and troubleshoot down to the thermistor on the thing. Put it back together and it starts working again. Did a load of clothe a week past that date and thing stopped working again. Tech come by a week later and determines that the Thermistor was bad. We replace that machine with a different one and all is well for the next 4 weeks then the same thing happens again. This time a different tech comes by and takes apart the vent from the outside. Machine works and we figure maybe this was the problem(although with a run to the outside that is all of 15 inches long and a straight run at that I wonder). Anyway that was yesterday and the misses reports that we got the stupid little code saying that it was messed up yet again, only thing that has changed was I bought a new outlet (much simpler to use) and was tested yesterday without a problem.
At this point the only thing we can conclude so far is that this machines are very very fickle at best (normal exhaust vent seems to maybe cause them to shut down) or are in fact pricey well you can think of some ways to finish the sentence at worst. All I can say is the next time we are looking for appliances I will not allow anyone (wife/salesperson) to sell us something that is not established. I originally had set out to buy a frigidaire unit. If I need a TV or camcorder or some other piece of Hi-tech equipment/gadget then Sam sung has already established itself. For Appliance though. Still has a long way to go.