This is a big reason for my changing over to medium format. I wanted to be able to swap films mid roll and I didn't fancy spending the kinda money that Rollei 3003's go for so I bought an ETRS.
My 35mm stuff has relegated to the drawer since I bought it.
The other option I used to do as well was to have two cameras, one loaded with the slower film and one with the faster. I just couldn't deal with the hassle of swapping films mid roll and the extra chance of blowing the films due to light getting onto it.