The IPA I'm drinking now is like grapefruit juice- in a good way. (Well, not RIGHT now- it's 8 AM here, but I have it on tap now!) Definitely grapefruity from the late addition of amarillo hops. Cascades has a little of it, but I've never noticed the citrusy taste in chinook, cluster, or simcoe. To me, simcoe has more resiny, piney notes to it. I usually use simcoe and amarillo together in my DFH IPA clone.