I've ended up doing both. Am VERY happy about the ISI open bronze/silver/gold levels, as they allow much more freedom, as does the new "you can do any spin at any level" rule. For a recent ISI competition, I only had to change a jump (which I didn't really "have" and wasn't passing to USFS standard anyhow) in my USFS freeskate program. And like Skittl, I like (1) the much lower cost of ISI and (2) the variety of events--footwork, artistic, interp (ie, improv), jump/spin teams, compulsories, etc.