I've got a beautiful little USFA Lightning carbine (but with a rifle buttstock) in 44-40. It's always been very reliable and is a lot of fun to shoot. I also have a Pedersoli rifle in 44-40.
You've chosen the correct caliber. The bottleneck cartridges feed well in these rifles, while the straight walled cases have issues - they weren't designed for them. If you stick to the 44-40 and either a USFA or Pedersoli you'll find it a really fun rifle to shoot and lots of folks at matches will say - "I can't believe you have a Lightning that really works!"
One other thing to keep in mind - it takes a while to train your muscle memory to properly operate a Lightning when transitioning from a lever gun. It took me 4 or 5 months to operate one smoothly. Initially, I'd find myself still trying to lever it while "half" pumping it. It made for some comical moments - after the fact! This is probably also one reason folks don't like them - they don't work through the transition period while learning to operate them.