I've worked with both rounds and for my own use,I'll take the 300 over the 338 for a few reasons.The 338 just costs too much to shoot enough for me to be proficient with it at the range it shows its stuff.They can be hard to get along with unless they're well built and well tuned.I despise muzzle brakes and the noise and concussion that goes along with them.My 300WM hunting rifle isn't the most pleasant thing to shoot because it weighs a little less than 8 pounds ready to hunt.A 14 pound rifle would be much more pleasant in 300 WM,but wouldn't be much fun in the 338 with a 300 grain bullet loaded wide open.A 300 with a 220 grain bullet can do lots of things way out there,but not as good as the 338.Is it worth the difference?Probably not to me.My last build,a 280AI heavy barrel is at the edge of what I consider comfortable to shoot during a day's worth of shooting long range.It's heavy enough to mitigate recoil and hold good,but I made the mistake of taking it deer hunting a couple of weeks ago.A 20 pound 338LM would be hard to tote very far up the side of a mountain for me and my 60 year old worn out back.