if you want to benefit from higher quality efx processing, why not to work on 96khz right from the beginning.? there is no need to upsample and then downsample back to 44.1...
I think that the difference when switching from 16bit to 24bit will be well hearable. but i am not too sure about the result when working on 44.1 then 96 and then back 44.1... i think i will try it..