what about using one of those sinking braided leaders (loop to loop) to change a floater to a sinktip. Could be a cheaper option (and faster to change) for someone starting on trout...
Does this system work out ok? or does it negatives out weigh its pluses?(I think it does, but then I don't really remember any record breaking catches with it either)
In any case a floating line will most likely be the best investment as they are (in my experience) the most versatile line you can choose.