I have both in browning stalker and love them both,both shoot better than I can.Took one deer with the 270 last year to try it out,will probably do the same this year with the 300,but usually use a 260 or 7/08 for deer.
Just got the 300 2 weeks ago so haven't shot it past 100 yds yet.but it gave some tight groups @100 so far.
Tried some 110 gr v-max in the 270 and they were awesome using r-19