The catala is a decent reel for the money. You should get the 300 size for 15# and use the 400 for 20#. If you want to switch lines/use it for both, just get the 400 and an extra spool from shimano. The 400 will hold more than enough 15# for bass so that's why I suggested using the 300 for 15#. Personally, if you're getting one bass set-up, 15# is a good all-around test to use.

--David

Big Hammer Swimbaits-Hammerhead Jigheads
www.swimbait.com
Pro-Cure Scents
www.pro-cure.com