I own the D4... predecessor to the D4R. I picked it up at a pretty steep discount, and sat on it for a while, figuring that anything with so many moving parts and such a thick manual was going to take some time to understand. I've been a hand-tool, hand-cut DT kind of guy for years, so ignoring the Leigh was pretty easy to do. (Still is, I like cutting dovetails)
Turns out the manual is beyond clear, and it took about 20-30 minutes to get used to the thing.
Adjustability may seem like it's just adding more finicky adjustments. The joy of it is, you draw a line where you want the sockets cut, at about the spacing you want, and move the fingers to those positions. Doesn't have to be perfectly spaced. Just good enough. It looks better than a regular Porter-cable jig, for sure.
And it does a lot more, that I'm still playing with. It's hard to tell what's redundant with my other setups and what isn't. I have a feeling it's all good.
Can't speak to the Akeda, but I've heard stories about supply problems with them off and on for years.
if the thing that's really bugging you is the possible discontinuation factor, I think you should put that aside. There are plenty of good dovetail jigs out there.