I substituted the Fish Lips Kiss heel for the one in the pattern. I really love this heel and will probably use it again. I still hate knitting toe up though. When I was finished and cast off the top edge had a sort of ruffle to it, which you don't get when knitting top down - and I hadn't used JSSBO, which I know can cause that.
Anyway, an enjoyable knit, the yarn pooled exactly as I hoped it would and I have my new socks on my feet right now, keeping my toes warm on this cold, rainy day.