Student Pilot,
I've installed the flap gap seals. Customer said he got 200 feet a minute improvement. ??? I can't verify because I did not participate in a before and after flight test and do not know the enviromental conditions. A local pilot who is also an A&P installed them on his 172. He noticed a similar improvement in climb performance and a very slight improvement in cruise, however his mod was done in conjunction with engine major.
Del

I've been thinking of installing flap seals on my 150F and would like to hear more from Cessna owners about their take, on whether the expense and weight penalty make them worth it.

I've decided not to fit any, the Aircraft is a nice light one and I'm quite happy the way it performs at low speed. Hav'nt got many actual glowing reports so when in doubt leave it stock.