How many foam ipa's have you had? I could see a few problems with some of the beers I've had at foam but I personally have only had the smoothest, fruitiest, juiciest ipas from foam. Describing them as sour makes me think you have either not tried enough ipas there or not sure haha "sour" just isn't not what comes to mind when I think of foam ipa's. Like sip of sunshine is a harsher double IPA if you ask me. Again, Ive had 10% doubles at foam that are smoother drinking then 99% of most 6% singles etc. Then they also have just out of this world layered fruit and flavored ipas that are like visiting the willy Wonka factory as far as the flavor trip you go on in just one sip. Haha loool sour is just not a great description to me lol.