What's an SP?
I took five years in a fairly odd way. I went to a small catholic college first year and switched to a good university the next year. I repeated several classes because I wanted a good science grounding even though my grades were fine - I wasn't all that sure of the earlier college. Took another four years all together at the university, piling up courses past the necessary requirements to graduate, learning hungry. Worked near full time (we weren't supposed to back then, took a million buses, spent those four years tired. Changed majors in there a few times - started at bacteriology/microbiology and finished with it.
Sometimes I had mediocre grades and a few times I was best in class, albeit small classes, not the ones with 200 students. I never saw a counsellor. Who the hell had time?
I wouldn't have missed that for anything. My world widened greatly.
This also was long ago.
I agree with Boomerang about a gap year or two being potentially a good idea; agree with Max on the gap in the middle idea also potentially being good.