Actually their DSO's are at or under 30 days. It has not deviated from that time period for years. Collections are not an issue at all. As noted in the last conf. call (or the one before that) their auditor makes them reveal if DSO's change to any significant degree.
You really should take some time to read thru the analyst reports on their website. Obviously many are quite old but the ones reflecting the initiation of coverage (around the start of last year) talk about the business model in great detail.
Also, Jim Preissler will most likely answer any other questions you may have over the phone if you set up a time to speak with him. I wouldn't bother with Bill Schmitt from ICR since Jim is much much better informed as he is involved in the day to day.