In the interest of full disclosure, I did purchase windows from these people a while back, and I do love the product. The windows are fantastic, they have held up great and they work as advertised. Top notch quality, and absolutely no complaints on the product itself.
So why, you ask, the 1-star? That's all down to the people working there and the way they conduct themselves. To start with, the sales guy we worked with was a real piece of shit. Had the temperament of a school kid, and when we called him out on trying to screw us out of a discount we were owed, he pitched a fit in front of my neighbors and threatened to walk off the property. This over a pithy 10% discount!
Not only that, but the guy had the balls to tell me, with a straight face, Tell your neighbors where you got these windows, but don't tell them what you paid, since everyone's situation is different. He seriously expected me to be coy or dishonest with my neighbors, just so he could try to screw them out a few grand more than I paid? Wow. And what's more, the asshole even pitched their referral program, so if I was willing to bullshit my neighbors, I would get a kick back after he bent them over!
Better still, the company continued to hit me up for additional business, even after I no longer had any windows left to replace. Endless cold calls, all coming from different numbers, but always the same knuckle draggers calling from the same local office. I nicely ask not to be called, tell them I love the product but don't have anymore windows, but it does no good. They keep calling. I talked to managers, I talked to supervisors, I heard every excuse in the damn book. We have new people here, and then it became, we just got new computers or we just got a new auto-dialer and we're working out the kinks, and finally, my favorite, our system crashed, we lost the do-not-call information. This went on for several years!
Bottom line, you should avoid these douche bags at all costs. Sales people are shady as hell, and the people working in their offices are dumb as a fucking post.