Both should work fine. My wife will be using either 180 or 200 grain swift a frames from her 308 win for her Kodiak brown bear tag this coming spring and I have no doubt it will work just fine.
A 300 RUM shooting any quality bullet will be more than enough. Go with whatever the gun shoots better.
That said I didn't even know they made a standard 210 accubond. If you are talking about the long range accubond then I will pick the 200 standard accubond over the long range one if sold on accubonds.
200 NAB or NPT would work well, I'd think. Really same for sturdy 180's. Woodleigh also makes a 200 protected point version for the 300 Win Mag. Given the "impact velocity" window up to 2900 fps, it may be a candidate for your RUM. Midway has them here