We are completely satisfied with the installation, quality of the product (front door) and follow up service. We had a minor flaw in the glass and the service department promptly addressed the issue and replaced the glass insert. QSI gets top marks for standing by their products.Tom, Hamilton

QSI did work at my grand parents house years ago. Had them do our upstairs windows. Great workmanship, quality and service. The new windows are much quieter since we do back on to a busy road. Also notice them to offer much better insulation. Highly recommend QSI to anyone.Mark, Ancaster

We are very impressed with QSI. The installer’s are very professional, and they got the job done quickly, but were very efficient. In every way we would rate QSI excellent!Gramigna, Smithville

Just had two new windows installed. Competitive price but best part was attention to detail and cleanliness during installation. These guys are efficient and competent and the new windows look great! Well done. You’ve earned a repeat and loyal customer!Glenn, Burlington

We had our original windows replaced in February. These guys were quick and friendly! What a difference the new window make with keeping the house comfortable. They did a beautiful job and I wouldn’t hesitate to recommend them to anyone (-:Jennifer, Hamilton

QSI provided a great experience in our purchasing of replacement windows, and doors. Their experienced crew very efficiently installed the new windows and doors, and the quality of product was excellent . Clean-up was super and there were no problems. We were extremely satisfied. James their salesman was terrific in suggestions.Robert, Ancaster

Phenominal. The workers worked very well together. One did one thing, while the other did something else. They cleaned up everything both inside and out. The cost is a little bit higher, but it is money well spent. I would use them again in a minute.Jim, Haldimand

I would like to say that i had QSI come in and give me a quote on windows then we decided to go with them and we got our windows on the main floor done and a couple of the basement ones done. They did a excellent job and they did it in a timely matter and cleaned everything up. I was very happy with the service from them.Diane, Hagersville

Sales representative was very professional and helpful in selecting the product and style they we were looking for.. the product had a slight defect and the representative was very responsive to our concerns and the result was very satisfied customers. we have employed this company many many times over the years and have yet to be disappointed in their workmanship, product line or professionalism.Sally, Farmington

We needed windows replaced in our entire house and had QSI supply and install the windows. They were very informative during the consultation and measurement appointment. When the installers arrived, they were polite and professional. They took their time in completion of the details of installation, such as the appearance of the caulking and cleaning all of the windows when they were done. They also finished the inside of the new windows for us.Lou, Brantford

The windows are wonderful, quiet, and much warmer.The men did great work, everything placed in to a tee. The windows were framed with nice solid wood,not plastic or skimpy looking wood, nicely mitered and cleaned up after the job was finished. They took all the garbage away and left nothing behind. This job was done over a year ago and we are still very happy. Thanks guys.Brenda, Beamsville