I tried the mixable starch and was not a fan...perhaps I was being to liberal with it, but the concrete floor of my basement was REALLY gross after trying it out. :)
I like sizing but also like to use Best Press. I normally buy a bunch of it when it's on sale at Hancocks, and they started carrying the big refill jugs there as well. It's a lot less expensive there, than at my LQS.
Just my 2 cents. :)