I just read the owners manual for Remingtons "new" 700 muzzleloader.
First, I don't believe it's a better system, just more complex than necessary and very well advertised.
Second, it is in my opinion very much over priced.
Third, they are using 4, 50 grain pellets to acomplish what Thompson center did with their Encore ml with 3, 50 grain pellets. The Encore is also a legit 300 yard rifle.
In either case, like Pappa G implied, it will take more than a casual shooter to make clean killing shots at 300 yards with either rifle. A two foot trajectory in addition to a projectile that is extremely suspetable to wind drift simply means you better be a well trained rifleman and well practiced with your 300 yard muzzleloader. Maybe one out of a thousand muzzleloader hunters will fit the bill. Maybe less.
However, the beauty of this thing we do (hunting) is that there are nearly as many ways to accomplish a common end result as there are hunters. I choose to hunt with a flintlock Pennsylvania longrifle. If you choose to use the latest most technically advanced weapon made, go for it. The bottom line is we both hunt. That makes us friends who have never met, not adversaries. Best of luck.