DelphiGlass was my first go to for stained glass and supplies. The website is very well laid out and provides good examples of what the glass color and texture looks like. That is good when you are not able to make it to see the glass in person. There are not many (or any) glass retailers in my area. So finding DephiGlass was great as a beginner.
A few pros, as already mentioned the images they provide for their glass selection is great. They show the color and texture the best they can with having is on the web. I have never been disappointed with the glass I get not matching that was on their website. My expectations were met. Another pro, is that they are willing to help. If you find yourself with a piece of glass you can take a picture and email them with a description of what you have and they will try to find the exact match for it or something very similar.
A con that I have, is that pricing can be a bit out there for shipping. After finding other glass retailers online I believe DelphiGlass is a bit high on their shipping costs. Will this deter me from buying from DelphiGlass in the future? No. It just means that I might buy less often or wait until there is a sale or have a big order for glass that will justify the price for shipping.
All in all DelphiGlass is a good resource for anything related to stained glass anything.