I no longer own a .300 Mag of any make/caliber but that's a personal choice. As a handloader I weighed the benefits of what I got in performance, price, pain etc from shooting a belted magnum or any magnum for that matter. To me, the rewards were few and the negatives were many. I shot a .300 Wby Mag for years and thought it was the best thing since sliced bread and I still love to shoot my No.1 7mag but its expensive and not a go to gun nor needed. But dead is dead and my little 7mm-08 kills them dead as a doornail if I can see them in the scope. I wouldn't be scared to take one of my 30'06's for just about anything out there unless it was a Cape Buffalo, Lion or some big African game then again I haven't been to Africa and have no desire to go. If I want to hunt a bear then I'll take my .338 but I don't shoot it more than a couple of times a year.
Its all personal preference and what you want to shoot. One thing that I have noticed from people shooting the magnums is that many bought these guns that shoot a pound of powder each pull and every time they flinch. Especially after a couple of rounds at the bench, it gets to their head and their afraid of it subconsiously. If you can't shoot it effectively, practice with it practically and be steady when it counts it doesn't matter. Hunting is about shot placement first and foremost. Heck, I got a neighbor that has killed 4 deer this year with a .204 Ruger, not one took a step but they were all headshots and he's really comfortable shooting the gun.