We have an older house (1975) and had these guys replace several doors and windows on two separate occasions. The first job was smaller (2 doors, one window); it seemed to be done alright, so we gave them a bigger one (7 windows). What struck me right then was that they magically managed to do the second job faster than the first.
Shortly after (it was around Christmas '15), I discovered that cold air was blowing in next to one of the new windows. This summer, I finally got around to fixing this up when renovating the room - I saw practically no foam insulation on top of both windows. Then, last week, I noticed more cold air blowing into the kitchen. I decided to rip the trim from all their handiwork and get to the bottom of it. Overall, among all the 9 windows and outer doors, there were two (2) that actually had been properly insulated. In all others, there were smaller or larger gaps. In one case, I could see right into outer space from within my kitchen. In another, a stretch of some 20 inches was entirely without any insulation foam (see picture). That means to me that they did not even pretend to do a proper job; they cared only about finishing up on time, slapped on the trim, and cashed their check.
The quality of the windows themselves is fine, but then, they are not manufactured by Beingessner. Apparently, with these jokers, a $10,000 price tag doesn't cover proper insulation. Take your money elsewhere.
Oh, and my dear Beingessner, if you read this, don't bother with the "this guy no longer works here" schpiel. Your manager did not give him enough time to do a proper job - nobody could have done it properly in that single day of work you allowed for it. The fish rots from the head down.