I find "use base qw( Blah::Blah Yadda::Yadda )" to be a lot more readable than @ISA manipulation. This is probably because for a long time I thought ISA was a bus type, and I still have trouble reading "is a" there, in all caps. That said, it's not as if I spend a long time being confused either way.

I've used base in my own code quite a bit and never had a problem.