I almost bought a DE in .50 AE myself, I had been calling every LGS in my area and found that had one in stock. Ended up falling in love with a 1911 as soon as I walked into the shop lol. I still held the DE, and I gotta be honest, it felt FANTASTIC! I don't have particularly large hands, but gripping it did feel nice

I'm also 6'1", weigh in at a MASSIVE 170 lbs. LOL. Shooting that monster would likely yield unwanted results for me though, as in a DE imprint on my forehead lol. They are of pretty good quality from what I understand, I'm personally not a fan of the newer ones just because Kahr arms owns Magnum Research now, and I simply do not like Kahr arms...personal bias. I like the older ones though.
IMO, if you are determined to have a large caliber handgun that you want to use, get like a S&W .460 X-frame revolver, if you don't wanna shoot .460, that's fine, pop in a .454 or a .45 LC. The joys of multi-cal firearms! If you must have the big .50, get the S&W .500 magnum, there are some weaker loads for that as well. If you want a big gun now but don't have a big bank roll, check out the Taurus Raging Bull in .500 magnum or .454 Casull, both big on power. I'm no real fan of Taurus, but from what I understand they've stepped it up in quality a lot recently.
The Tavor is also a really nice choice, I love bullpup guns! I don't know a whole lot about it being that it's new and I live at work but me and my boss have been eyeballin' em' for a little while now lol. They seem to have really nice features, I like the integrated sight system.
The Kriss Vector *Homer Simpson moment of the day* GLAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHHH *insert drool here*.
Going to get it in SBR form, rifle or pistol? I'm fond of the pistol myself, and if you ever decide to go class III all you have to do to make it an SBR is pop a stock on it

expensive though.
I like the Super V recoil system as well, while I haven't personally fired it, my boss has, and he literally fell in love with it, and is about to buy one here in the next couple months.
I also like the fact that .45's are cheaper than .50's
Let us know what you buy first and post some pictures ^^