Mmmm...depends, as others have said.
The Guide Gun is too short, and too loud for my tastes. The regular Marlin .45-70 seems like a good rifle, for general use. The long barreled version should be fine, too.
I really would like to have a #1 in .45-70, just because it has an exceptional balance and class. That said, Browning's traditional Hunter in .45-70 is also a really nice rifle, if you want an iron sighted .45-70 single shot. It and the Ruger have very strong actions, that allow full explotation of the round's potential.
There's also a variety of sharps rifles out there, from Shilohs and Dakotas that are works of art, to Italian copies that are decent.
Original Trapdoor Springfields can be found in shootable condition, but you must be a competent handloader to take advantage of them. Repros are a better bet. H&R sold an "Officer's Model" TDS a few years ago, and it was a nice hunting rifle, fairly light.
There are a number of Remington Rolling Block replicas out, that are solid rifles.
And yes, the Win 1886 is out in a lightweight version. Folks now say this rifle can take any load the Marlin can handle.
I think there even a few Stevens 44 & 1/2 and Ballard replicas out in the caliber. And...
...I read somebody was trying to build an autoloading .45-70.
of course, a .50 Beowulf sorta is the same thing, sorta.
