I sit in 15 foot ladder stands all the time and they work fine for me. A 20 foot may be some better as far as scent dispersal, movement, etc, depending on where you hunt. Your sight area may be more limited due to limbs, etc with the 20 foot. Get some hardened steel 3/8 chain and use a big lock on your ladder stand. Use a climber to get under the stand to lock it to the tree making access with a bolt cutter harder to do.