Just how much mud are we talking? Is this trying to ride uphill, is it on sections that friends / others appear to clear easily? Perhaps you may want to look at your technique first, before looking for new tyres? If you are trying to ride through a bog or a ploughed field, sometimes you are going to come unstuck.
I run the classic combo of Minion Front / HR Rear, and cannot fault the grip. I have found the mix to be quite draggy however, and used to think it was the Super Tacky Minion slowing things down, but it is probably the HR on the rear TBH.
Now that they are starting to wear, I am thinking about switching to the On-One Chunky Monkey Front / Smorgasbord Rear combo that has favourable reviews on here and seems insanely good value.