I know the feeling. I purchased a new Mogul early 2008 and had no problems with it until the End Call button was troublesome. I dealt with it until I dropped my phone and then everything went downhill.
I got my replacement from TEP that had a bad WiFi card. Then another with bad answer/end call buttons and WiFi. Finally the third refurb that came in that week worked fine except the scroll wheel on the side never worked correctly. I cut my losses and for the past several months until today and dealt with it.
I went to the store today to have another one ordered from TEP. I just can't wait to get another defective refurb! YAY!
Oh, for the record, my current Mogul has a hot spot on the screen but it's not all that noticable.