I have been using MSR Groundhog stakes for ages. Bought about a dozen of them a long while ago and have been using them since. I've replaced the cord on a few of them.
I was thinking about MSR Needles to save weight, but the holding power of the Groundhog is too awesome to risk having to re-insert stakes to save a few grams. I would use the Needles with their squared edges before going to Ti stakes with their smooth rounded profile.