STIS or ACS?

The AstroDyke asks an interesting question: if NASA only has funds in the next Hubble servicing mission to repair either STIS or ACS, which should it be? My vote should be obvious: I worked on STIS for 5 years. But it's not just loyalty: Hubble lacks a good UV camera right now, and cannot take decent spectra at all in the optical or UV. ACS is a fantastic machine, but I think (I need to do more research, admittedly) that WF3 will cover a lot of the same ground sky. So what do you think? Leave comments on her blog; give her some love.