Rihanna & Eminem perform ‘The Monster’ at MTV Movie Awards...

Rihanna joins Eminem for the first performance of their hit single 'The Monster' during last night's MTV Movie Awards. Eminem was relying way too much on a backing track and I thought Rihanna's full chest voice was good sans for one thing.

It would not have hurt Ri to ask Ariana Grande to teach her how to whistle tone. Truthfully speaking, she really can't hit whistle tones.

Thoughts?