One is not better than the other gram per gram it is all the same.

The most important is to feed what works for your BP and what is convininet for you.

Personally I like feeding rats because I rather feed one prey than 3 or 4 however not all my BP agree with me so I do feed mice for those who refuse rats (4 out of 21 BP are mousers)

So if you want to switch to rat and it work with your BP go for it, if you like feeding mice better than it’s ok too.