I wasn't aware the 'Schuler' filters were discontinued ... must be fairly recent. I guess it was understandable that Don (owner of Astrodon) decided to change the design as the Schuler filters (he purchased the original Chuck Schuler business a couple of years back) were prone to all sorts of hygroscopic deterioration. I'm on my second set, and some of them are starting to degrade after a few years
The Custom Scientific BVRI filters sold by SBIG have a very good reputation, but were always more expensive (US$175 ea) than the original Schulers. Andover Corpalso sell photometric filters, but I don't know anyone using them (
http://www.andovercorp.com/Web_store/UBVRI/UBVRI.php)
In the amateur community the choice was always Schuler for cheapness or Custom Scientific for quality.