both are very good varmint setups just depends on what your willing to spend both deliver great results with good ammo but rra receiver's are better built than bushmasters(now made by Remington i believe) but you really cant go wrong ether wayI'm narrowing my selection of a varmint upper to the Bushmaster Predator 20 inch, or a RRA 20" varmint flat top.
Anybody have either and can share their experiences? to help me decide.