I would suggest the taller tub, I love watching our little guy climb all over the driftwood branches in his tank, if you are using real wood make sure to clean it very well and bake it.

Mine will usually crawl around at night time on his branches and then cruise to his hide in the day

* Like Starmom says I have a 4ft boaphile waiting for my little guy to grow up, I plan on picking up a couple more at Tinley park and they will get the same thing, tubs when they are small and the boaphile when they get a bit bigger