I have one of each.
Tikka is a 30-06, RAR is 308
Tikka is in my opinion, better in every way with the possible exception that the RAR is an actual short action.
I've not had any mag/feeding issues but again, it's a 308 (a cartridge designed to feed reliably in machineguns)
Also, there is a $200-$300 difference in price, at least where I live.

Bore size is no substitute for shot placement and
Power is no substitute for bullet performance. 458WIN