Good luck trying to find the 300 win mag. I waited 6 months and tried to buy one new...I ended up going with the 300RUM Sendero SF2 instead. Personally, I did not see the 300WM being worth the wait, when the 300RUM was readily available. I simply couldnt find it. When I called remington, they told me that the wait would be another 4-5 months for them to ship to retailers.
Then I got thinking that 300RUM, unlike the 300WM, is a beltless cartridge which will help you avoid headspace issues if you do decide to reload. Granted, 300WM is easier to find and gunshops and outdoor stores. If you intend to shoot alot and eventually reload, go with the 30 cal since bullet selection is much better than 7Mag. Load it up for varmints to grizzly bear...30 cal covers about anything... The 300RUM is friggin awsome. Asskicker and a stunner to look at.
I ended up mounting a Leupy VX 3LR 4.5 - 14 x 50, M1 windage and elevation, with Nightforce 20MOA Base, and Burris Signature rings. Weight roughly 11.5lbs which will help diminish recoil... The Sendero I have heard will hold 1/2" at 200 yards...Excellent Choice, 300WM is a great choice. Go for it if you can find it. I couldnt find mine, so I went with the 300RUM.... Happy hunting.
Just my 2 cents.