Consensus is people love these. Unfortunately, there's a steadily growing minority that have had one-time or chronic problems with these things. Clogging, cracking, ridiculous pressure requirements, and poor connection design have been issues.
This is aside from issues stemming from the cracking pressure, which can be anywhere from 25 to 45 psi or so.
edit - I've used 3 of these. Using one or more of these in a rig that feeds 2 or more tanks is, at best, difficult. However, individually, they tend to work very well.
Last edited by kevmo911; 02-22-2013 at 04:13 AM.
Reason: personal experience