I agree with "Don't fix what ain't broke." But your window sealing can be broken, and not look like it.
When I resealed my windows - in my trailer that was still under warranty - I found a major issue with how my windows were installed in the cut-out hole in that only one of them was centered in the hole. Since the hole is oversize (by design and by necessity) the window has to be centered with shims. Otherwise, the window will be at the bottom of the hole. Given the size of the window flange, the size of the cut-out, and the curvature of some of the corners there will be places where less than 1/8" of flange will touch the side it is "sealing" against. Any defect in the gasket and a leak results.
At the very least, I would encourage you to put a cap of caulking over the top of the window and down the sides.
Here is a link to a window re-seal thread I started:Window reseal thread (clicky)
There's lots of advice and information in forums... sometimes it is correct. For example, all of my posts are made by a political appointee who got the job as a reward for contributions to my diesel bill.
2011 Jayco 28.5RLS; 2008 Chevy Duramax; Pullrite Superglide Hitch