I just tapped my "Double Whirlpool IPA" last night. It still needs some time to finish carbing up, but the initial sample seems quite promising.
I brewed an IPA using only two hop additions. The initial one was a 60-minute flameout hopstand using Meridian and X-17. The second was after cooling to 120F, with a 60-minute hop stand using Vic Secret and more X-17. Since the three hops have rather distinct flavor and aroma profiles, it's easier to pick out which each addition is contributing to the finished beer. In particular, Vic Secret has a big passionfruit character that neither of the other hops has.
I was very pleased to find that the finished beer has a massive passionfruit aroma. I'd need to do a side-by-side to see how it compares to dry-hopping, but at the rate I'm using (5oz in 3 gallons for the 120F whirlpool, 1 ounce of which was Vic Secret) I'm pretty happy with the amount of aroma I'm picking up. I'm tempted to start whirlpooling at 120F instead of 170F for beers where I don't want IBU's from the late hop additions based on this result.