Crappy hub, okay to swap out and keep current rims?

[Love Commander]

So I remember from internet heresay that it's a no-no to remove a hub from an existing wheel and swap in something new. Something about a rim that's already been laced up and tensioned once will be a nightmare to true after a hub swap. Any truth to this?

I ask because I have a beater/lock-up bike I want to spend a minimal amount of money on. The freehub is toast, but the rim is A-okay. I could swap it out with a cheapo Deore hub and only be out the $ for the hub and new set of spokes. I'm not a stranger to building my own wheels, but I've always started with new parts. I would like to get some opinions before I embark on a potential fool's errand.

Thanks.

[One Pivot]

Any truth to this?

Not a drop of truth! Ive done it tons of times. No problems at all. The higher quality the rim, the easier it is. Some older rims that are flexy anyway can be a little bit more picky to relace but its still very manageable. Far from a nightmare and any semi-skilled builder wont have a problem. Rims like that are difficult to build when new too though.

Ideally, id like to lace up nothing but 600+ gram rims with straight spokes and brass nipples, because nothing is easier to build! Real world, ill lace up a 400g rim with revo spokes and alu nipples without an issue. Its harder, but eh. Far from a nightmare. Using used rims and spokes kinda falls in there too. Its not the ideal easiest build in the world, but lots of builds arent. I think a lot of bike shops are either trying to just make money selling rims and spokes, or they're too lazy to want to do a marginal amount more work.

Danscomp.com has sapim double butted spokes for 40 cents a piece.