Are they generally reliable, specifically in 44 Magnum?  Looking at a 6 inch 44 made in Israel.

Paladin

Regular hollow points got hung up on the feed ramp in mine.

I found some PMC ones that had a copper jacket up to the tip.

My dad had a 6" in .50AE that he carried in Alaska for bears

He hand loaded Barnes copper solids for bears (375gr IIRC) and plated cast for practice ammo.  It really was not bad in the recoil department if you are not recoil sensitive.  It recoiled less than my 4" 629 with hot loads.

If I were buying that heavy boat anchor I would go all out and get the .50 and skip the .44, but that's just me...  The gun is too big and heavy for .44

They only function with  limited types of ammo unless you reload. I had a 357 version years ago and it would only function with x1 type of ammo. The owners manual will tell you what to use with it. Like the other poster said, for the cost of the ammo, might as well get the .50.

My .50 functions fine if I make sure to have a death grip on it. If not it tends to either throw brass into my face or misfeed.
It's reliable as a range toy...no practical purpose for it.

In my experience, if you use proper ammo (full power, like American Eagle), I never had any problems based on the gun or ammo.

However,

I have large hands and a very high grip, and if any part of my hand touched the slide during recoil, the gun would not cycle properly. This was especially problematic when shooting in winter gloves.

Back in the 1990's I had a .44 magnum Desert Eagle. Prior to that I had a S&W model 29 6 1/2" .44 magnum. That S&W had a hefty recoil. The Desert Eagle on the other hand was like shooting a .45 ACP as far as recoil. Last year I purchased one of the new stainless .50 Desert Eagle. That cartridge is a handful for me. A lot more recoil than the .44 magnum DE. I did have the larger, wood grips OEM DE laser carved wood grips on the .44 magnum DE that I had in the 1990's. This new DE I put some aluminum Alumagrips on it and maybe that is adding to the felt recoil. In any event the .44 magnum DE was very easy to control and shoot for me. This new .50 I may have to experiment and try and find some larger wood grips for it.

I have the multi caliber kit (357/44/50) all 6". I've had it a long time.

I use hogue finger groove grips.

My 44 barrel is scoped. The others have millet target sights.

Winchester white box has run fine in all calibers.

.38 and .44 special shoots fine, but requires manually cycling.

Operator error has been the main problem with cycling. Riding the slide... Limp writing... death grip... Cycling problems happen anytime I let someone else shoot. I can't remember that last problem I had with it.

I can fire it one handed, but I'm pretty recoil tolerant.

Optics and sights can shoot loose, so loc-tite or staking is a must.

My Mk VII in .44 eats every factory load I feed it, though it seems to feed a little better with flat points instead of HPs.  It likes to eat fairly hot loads, so if you're reloading, keep that in mind.  

Fairly reliable as long as you keep it clean.  Mine goes about 100 rds before it starts to gum up.  A quick wipedown of the bolt and lugs, run a bore snake through it and it's good.

I had the 50AE in a 6", Israeli made. It never missed a beat after I learned how to hold it, my off hand thumb would bumop the slide stop under recoil causing the slide to lock back with rounds left and not lock back on an empty mag. I did have a few days when I shot a few hundred rounds and let others shoot it quite a bit too. Before I sold mine I was thinking of getting the 44mag stuff for it. If I had the cash to buy another I would...