I hunt in the Nebraska Sandhills and see the two regularly. The above info is correct. A whitetail buck will run off mule deer bucks to breed the does. The big 4x4 I posted in the success thread was actually chasin two mule does when I took him.
Now with the particular property I hunt, there is a river running through it. The whitetails tend to stay near the river and the timber. If you want a mulie, we go over the hills and spot and stalk. It's nice to have the ability to take either species.
Check your unit regs and tags though. I always buy ATLEAST one statewide buck tag because I hunt so many units over the three major seasons and your only allowed 2 bucks per year (firearm, archery, muzzleloader) and the statewide is season choice so if I don't get an archery deer I don't burn a tag. Only problem with that is I also have to buy a unit tag because you can't tag a mulie on a statewide tag. (it's whitetail only). Also, there are mule deer management areas where they are not allowed to be taken. So just heck your regs.
Rule on the 11,000 acres we hunt is atleast out PAST the ears, and ATLEAST 4 points per side. They are too easy to hunt as they always turn to look at you after a 100 yards of running. If you kill all the dumb young bucks, you'll never get the big 30 inchers.......