I'd take the last two tires off your short list, there are better options out there for similar money. The Big Horns and Reapers both get great reviews and are regarded as some of the top trail tires. The Pitbulls are undoubtedly going to be the toughest but also by far the heaviest, so if your not looking at clutching your machine you would likely experience a noticeable power loss with those, especially in 28". One tire you left off the list that you should strongly consider based on the terrain you listed is the Bearclaw HTR, few guys I ride with run them, great radial tire that perform well in all terrain.