Beg to differ. Unless they've changed the bullet length, they're too long to seat in a standard length case and feed through the action. I ran a long series of trials when the .44 FTX first became available. The handloading bullets had a slip in the box saying to trim back .050". I chose to cut back the stop on the carrier instead. The few factory FTX loads I shot had short cases, too. Still have some kicking around.
I abandoned the FTX when I found out the ballistic coefficient wasn't as good as the 240 gr. XTPs I had been using. I found the bullet jacket a bit fragile and tips ditto. Reasonable accuracy, but no better than the previous stuff and a lot more expensive, like twice the cost. Really no advantage to using them. They will do the job on deer if placement is right. Certainly if that's the only thing that's available, they'll work on game. But no magic bullet. You can search this forum for my past posts on the subject. I put 500 handloads through in testing and a box or two of factory loads. Currently using Nosler's 240 gr. hollowpoints, slightly cheaper than the XTP and holds together when the shots get tough. The FTX loads did feed like they were greased. Look sexy, too.
Marlin redesigned the magazine follower to handle the FTX, all that's needed if you really want to use them in an older gun is to get one and swap parts.
Stan S.