Varies from hunt to hunt. I hate for one (or a pair) to feel neglected for very long. ...and I just like to use different knives! The two different pairs below are the ones I use the most.
I use this pair (Yellow Jacket and #1 Semi) from Gene quite a bit:
I use this pair (Slitter and B&T II) from Charlie quite a bit as well:
First year to use this one, a Flat Rock Scandi by Charlie May. I'm really liking it.