Rel Storm and Rel Strata III

Can anyone tell me the differances between thses two? Is the strata III an upgrade to the original storm?
Let me clarify! Would the Strata III be a better subwoofer. than an older Storm? My system is B&K 4090 Citation 5.1 Amp B&W DM 620
I have the Strata III. The Storm is a bigger sub than the Strata. That depends though on what improvements have been made to the Strata over the years. My advice is to call Rel and ask them.
I had the Stata II and upgraded to the Stata III. The Strata III is about as poweful as the orig. Storm, but I still don't think it loads a room quite as good as the orig. Storm. The great thing about the Strata III, compared to the orig. Storm, is the ability to have different crossover settings for the speaker level and line level inputs (works great in my combo HT/2-channel setup).
I think the Storm is ported, whereas the Strata is sealed. I tried both independently but not together. I think the Storm was more extended, but not as tight as the Strata.