4 years on a rim is pretty amazing, I’d be surprised if I get a couple of years out of my Flow Exs.
What are you riding, and does it warranty a flow? IF it doesn’t, then it’s extra weight in the one place that counts for no reason.
If you find tyres hard to get on Crests, then you’ll have the same issue on Arches, Flows etc…
EDIT, those Mavic rims are pants.
Extra EDIT, what colour rim were you after? The black Flows on CRC are only 36h, as the white are 32h.
You probably won’t need to replace the spokes, if you keep the ERD the same on the new rim – but… what nipples do you have? Bog standard brass will come off easy, aluminium will probably have siezed on, and you’ll need to cut spokes.
Easy way to tell is… what colour are the nipples? If anything other than black or silver – it’s alu. IF it’s black or silver, you still can’t be sure.