I beg to disagree.
A 450 is a modern version of a 4570, designed by Hornady/Marlin made with a belted case so the higher performance loads cannot be chambered in a 4570. Problem with 4570 factory loads is they're very light due to the many old and lower pressure tolerance 4570's still in circulation. To put it bluntly, in terms of factory ammo, the 4570 is a wimp compared to Hornady 450 marlin ammo.(If I remember correctly, 1400fps vs 2100fps +-)
If you reload there's no practical difference between the two. 4570 fans will tout the 4570 case can hold more powder, which is true; what they won't tell you is a 450 has more mv, so the extra powder isn't "extra", it's "catchup". With the exception of brass, identical loading components are used, and if you like, load data. Neither is a "common" caliber, and whichever you get you'll have to look for ammo, or components, but it takes very little looking to find.
Browning makes a 450blr, marlin makes both. Despite 4570 fans being just as rabid as tikka fans, My best advice is between the two it comes down to a coin flip if you want a marlin, a 450 if you want a blr.
Can't help you with a 444. You can look on the marlin owners forum.