Having worked with both HIPS and ABS, I would have to choose ABS. It's a myth that HIPS forms sharper than ABS, just not true. What is true is that HIPS is easier to form for the hobbiest but, if you have the right machinery, ABS pulls just as sharp.
I used to work with .100" high gloss HIPS and it was great to work with. The problem with HIPS is that it does crack if stressed or flexed too far. The same can be said for acrylic capped ABS which I am using now in .80" guage, though it is tougher than HIPS and more flexible, it is not unbreakable. Regular ABS is a lot more tougher than the capped version and available in more thicknesses. It is, however, not as bright white in colour compared to the acrylic capped ABS which is a very bright and very glossy plastic.
There is just not enough rubber in HIPS compared to ABS. So ABS, by default, is the winner.