Hmmm... May I ask where do you live? Depending on the weather in winter you want to go with the more/less insulation. Same stands for Denie: if your horse is by himself, you may want to go with the lower one, if other aggressive horses in same field - with the highest one. Everything you posted is pretty sick.
I use just Saxon 600D with 180 g polyfill for 3 years in row (jeffersequiene.com --> search for Saxon blanket) and they still go strong. However I'm in MD (read, pretty mild winter) and my horses are togehter in ield by themself (read, don't try to rip-off each other blanket, well, almost).
Weatherbeta is a nice brand, and Dover is a good place to shop. I personally not big fan of Chick's (been there in person and they come to the Expo every year), because everything they sell seems to be on cheap side. BTW, don't be fooled by those "retail for" price. I don't think it's same as "sale".