I prefer TL because I like the theme better and it has more of the kind of slides I enjoy most.
I think the best water park attraction in both parks is at TL - Crush n Gusher. It's a water coaster - like a slide but you have some uphill sections. It is so fun! My friend and I rode all 3 tracks and it by far our favorite thing.
I found a lot of the slides at BB very short and not worth a wait. Downhill Double Dipper is less than 8 seconds long and we waited 45 minutes for. Not at all worth it!
Toboggan Racers were fun, but I would not wait more than 10 minutes for it - again, a very short ride.
We did not do Summit Plummet or Slush Gusher, but we rode all the other slides. Teamboat Springs is probably my second favorite water park ride behind Crush N Gusher - it's a family raft ride but it's really long!
More of the slides at TL have twists and turns, so you get more slide time for the wait. BB has more slides overall, but that means more lines, for very little slide time.
I liked the lazy river better at BB, it does seem to go slightly faster than TL's, and it has more shady spots.
Be careful in the wave pool at TL. I would not go past knee to waist deep if you're not a strong swimmer there. Every 90 seconds there is a 6 foot wave. When that giant wave comes, people underestimate how forceful it is and get knocked down.
The wave pool at BB is more relaxing, it has a medium bobbing wave to it, with periods of no waves.
I think which water park is better for you depends on the kind of attractions you like. If you want fast thrilling body slides, than BB is the place to go. If you like more mild thrills, but for a longer time, than TL is better.
