I had to sneak up to IPA's too. Some were just too damned bold or flowery for me--somewhat like Kai's example on chili but I likened it to some darjeelings--one of the more flowery of the black teas. Too much floweriness can be overwhelming making the drink sippable but not necessarily enjoyable to the fullest.
Stone really wants to pack that punch, it's why they name their brews stuff like "Arrogant Bastard," etc. But I still love 'em, they've grown on me like a favorite mole.
I think I've mentioned before how jealous I am of your proximity to Stone. Harpoon isn't too great a distance in this area, and I do love them, but Stone is just pure balls.
I really don't actually enjoy most standards IPAs. They tend to finish poorly, with a bad, almost dirty aftertaste. I find most double or super or other extreme IPAs finish clean and crisp, almost like a palate cleanser (even though it's probably because it's a palate destroyer). I'll avoid Mayflower and Harpoon IPAs, and really even 60 Minute or Stone IPA, but I love the alternative 90-Minute and Ruination. Cascade hops are probably my favorite variety because of said strong flavor without the sour aftertaste.
For those of you who are looking for a flavorful and drinkable IPA, every year at the hop harvest Harpoon releases the Glacial Harvest IPA as part of its 100 Barrel Series. They're added to the brew fresh and wet as opposed to dried, and wet is really the best way to describe the taste difference. Smooth and delicious as hell.