Issue with older Roto on newer performer?

[LightningBoldtz]

I have heard that the older Roto does not fit performers, I have a SS version and it seems to fit fine, what is the issue with this and can someone elighten me on what the issue is with the old roto and performers?

Thanks

[pbe gummi bear]

The only issues are the roti lip may hit the lid bale bolts and you can't use the lid bail.