Are rex rats largely impossible to tell apart?

I know that rex rats have curly hair, but is it the same compassionate of fur? ie waterproof? or will they drown? I have a hooded normal rat and I love her to bits but I find her fur a bit wirey and be wondering if I were to buy a rex rat, is it the same, a short time ago feels and looks different?
i don't contemplate they will drown because rats are good swimmers but he/she will need more time being dried
they tend to have thicker fur, so will soak up quite a bit of water, but they shouldn't drown as rats are excellent swimmers
Answers:    A Rex isn't going to drown because of it's curly hair.
Rats are super swimmers :)

Edit: Her fur might mean that she requires somewhat more time being dried.

It's great that your rat enjoys bathtime, a couple of mine were relatively scared at first, plenty of toys and shallow water helped and presently they love it!
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