I debated long and hard as well, as 550cr for a sleeve is steep. But I have used them for about two months, but probably have not played as much as when I used the Callys.
Are they good, yes, longer and more spin but as Jim says, it take minor adjustments on spin - and to be honest I think I had the measure on the Callys, but I am not quite there with the Nikes - OR WGT is playing havoc lol.
But I suppose you have to ask yourself, what can you buy for six bucks these days?
Crap, I forgot you like in the land of cheap - Rolexes, plastic surgery and women. Yes they are pricey!