After getting quotes from a few of the top homestars companies, I found that:
1) It appeared that the main complaint from people revolved around the time from order until the door was ready
2) Excessive delays
After seeing that the quoted prices were quite similar across the board, I chose to proceed with Doors and More based on Frank's timely communication / responses.
The door was ready as promised within a couple of weeks, and as promised it is installed in my shower stall now (after a quick 30 or so minute install).
The installers were very careful with the property, and cleaned up quite well.
In the end, I believe that the 'immediate install' for my specific job was simple enough that most companies would have been fine, BUT, here is the important thing for me: Frank comes across as a man who takes great pride in his company's work and reputation. I feel comfortable that if there are any issues Frank will be right there throughout the warranty period to rectify the issue. That's key for me!