Well, I'll offer my (unbiased) views on the subject. I've been to 10 SF parks in the USA (haven't been to SFFT, SFoT, SFMW, SFEG, SFAW) and based on my experiences, I think SFGAm in Illinois is the best overall park. It will have 12 coasters this year, among them are Raging Bull, my #3 steel, and Viper, a top 10 wood. It has a great selection of flat rides, albeit they are somewhat older. The operations are fast/smooth, the food is basically good, and the shows are some of the best.
Other SF parks I enjoy immensely are SFWoA (operations stink by my goodness, do I love their coasters!), SFMM (pretty good coasters and operations, beautiful location) and SFGAd (awesome selection of coasters, tons of newer flats, but *pathetic* operations, tons of staffing issues).
SFNE, SFoG, SFKK, SFDL, SFA, SFStL all could use some more rides, and MUCH better coaster operations. SFoG has the best rides out of this group, but the operations are horrid. SFDL operations are decent, but they have all of five coasters! They need a better ride selection. SFKK has okay rides, but one train as the norm is pathetic. SFA, when I visited, had decent operations and their rides are really good, I thought.
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"Yes if by crestfallen you mean KILL US!" -- Homer J. Simpson