BB has better, more thrilling slides overall,but TL has a better wavepool and nice lush theming,it also has the shark reef to snorkel with small sharks and tropical fish and Crush n Gusher which is probably the most unique slide in either park.Aside from Crsuh n Gusher the other slides are mediocre to okay with the Humonga Kowabunga body slide being the most thrilling.Lazy rivers at both parks are pretty equal.I prefer the layout of TL where things feel more spread out since at BB most of the slides are up the mountain so you have to continuously go up the same 2 staircases,which gets tiring and boring or wait in line for the chairlift which only gives you access to two slides anyways.One of those being the family raft ride which is about 50 times better than the one at TL,which is pretty awful.BB also has the more unique theme but the glare of the sun on the fake snow can get bothersome at times.If you could only visit one park and prefer the more thrilling slides then do BB,however TL is probably more popular not because of the slides but other things it offers like the atmosphere and unique attractions like Crush n Gusher and the Shark reef.I honestly couldn't give you a favorite between TL,BB and even Aquatica the waterpark at Sea World,they all have things I love so in my opinion all three are worth visiting.