Chris,
If the lift capacity of the CT335 is close to the DK35, you'll probably be just fine unless a large FEL capacity is your goal. The loader on my CK30 was a couple hundred pounds short of my needs, the DK35 would have been just fine. Other than larger front tires and axle and a smaller FEL, the CT335 is the exact same tractor as the CT440/445/450, and they are brutes. The CT335 is also only a couple hp short of the CT440 anyway, so if it's PTO stuff you're looking to do, you won't see a difference. I would be looking for a large enough difference between the price your dealer is giving and the price of a CT440.