They're $12 at CVS (I got them for less b/c I have the CVS discount card). You can probably find them for less at Harmon's. I picked up the navy and purple ones-- both of which have shimmer.
Fluidlines are $14.50 for 3g of product, the HIP ones are $12 (or less) for 4.5g of product, so you do get more for your dollar with the HIP ones.
As for staying power, I swatched the blue one on my hand: it stayed put under running hot water, and only faded a tiny bit when I scrubbed with soap. It only came off after I used Lancome's Bi-facil on it. So well worth it, imo.
The only thing I don't like about them is the brush that they come with-- it's a bit coarse and wide for my tastes (more like a brow brush than a liner brush). Also, I prefer a longer handle. Haven't tried applying the liner with this, but you're probably better off with a real brush.