If you can, use the planer. It turns good strips into better ones.

It will definitely save you time later, and may spare you from some of the messiest part of the sanding. You'l also save on the cost of a few sheets of sandpaper.

With nicely planed strips you can fair the hull more easily as you'll see that all your high spots will be along the joints. You deal with fairing, and only fairing. No need to try to fair and also thin down a strip which is standing a bit above its neighbors beause it was ripped a wee bit thicker than the rest.

With all the strips planed to a nice even thickness all that work is done in advance by the planer. You end up with pretty, nice smelling shavings which sweep up easily, and make a nice mulch in the flower garden, rather than a roomfull of swirling dust.

If it matters, I already put my money where my mouth (or keyboard) is and bought a DeWalt planer for my next stripper. Straight from the store it does not like to work on such thin strips, but by laying a sheet of plywood on the bed (and clamping it down) I can raise the work and can plane very thin material. While waiting to build the boat my neighbor used it to strip the finish off of a roomfull of oak flooring, and I've used it for making windows. Eventually it will get used for the original ( boatbuilding) purpose for which it was purchased.

PGJ