Good advice from the Lady. Personally, I would go for the intermediate sink, maybe a type 2. The inter is a very versatile tool. It will still sink deep as LF says but you just have to count a few more seconds, not a big hassle in a lake, as you have the time generally.
A sink tip you can more or less replicate with flouro leaders and some weight on a floating line. Don't forget you need an extra spool for each of these lines, that it the big expense.
One last thought, this week I got to fish some cheap sink lines against some good branded ones, and don't buy cheap. They sink at different rates, are generally all over the place. You get what you pay for so if you had an intemediate and some flouro leaders and weights you are well on the way.
"We do not inherit the earth; we borrow it from our children."