Getut . . . no comparison is perfect. We tried.
But what I do know is that a lot of people put bucket hooks on their FELs and then lift something heavy and the top lip collapses. By the definitions we used in this thread, I think it is safe to say that a H.D. bucket has a low likelyhood of bending while a L.D. bucket MIGHT POSSIBLY be more likely.
I also know that some manufacturers offer multiple buckets for the same loader. JD offers at least 2 buckets on most of their tractors and their HD bucket is pretty darn beefy. Smaller tractors generally have lighter buckets than bigger tractors (hey, that makes sense!). And if you don't have bucket hooks then none of it might matter to you.
Similarly with bucket shape. A "C" shaped bucket might hold more stuff and might protect the hood of the tractor better when the FEL is in the full up position (which would be a benefit) but it conversly could be easier to overload than an "L" shaped bucket. Again, it really depends on the uses of the operator and what is important to them.
Look at the loader lever position. I consider that really a matter of person choice, but I also think that it is easy enough to get used to anything. Does it really matter if you move your arm UP and DOWN to dump the bucket or if you push your arm FORWARD and BACK? Interestingly, JD seems to offer fender mount on many sizes of machines, NH offers fender mount on larger machines and loader mount on smaller units, it just is what it is. Some will find one more comfortable than the other. But they are different. And each person can figure out if they like one or the other, or if they don't really care!
I wanted to include 5 pictures of each, and show the operators platform from the left side of the tractor. I honestly could not figure out a way to OBJECTIFY the view. But I can tell you that some tractors are easier to get into and out of, and I can show you why, I just think if I do that someone will say I am bashing their particular tractor.
There are other 'comfort' issues that can be discussed as well, but those really fall into the SUBJECTIVE issues. So I don't want to go there.