It's true, long cycles are really not a problem 99% of the time, it's just that we've been used to the 40-60 minute cycles since the introduction of dishwashers.
I've had GE dishwashers for decades and really like them. The pump went out on my current Ge, ordered the parts - all of $19 -- but never got around to putting them in, I will at some point. Got a heck of a deal on a KA and decided to try it. It cleans VERY well, no issues. But it can take hours, but it does have a 60 minute cycle I've used from time to time. Surprise it uses MORE water to do the job in less time on the short cycle.
For me the jury is still out on the racking, having used GE products for many many years I am used to the racking and knew where every item I own would fit, plus the racks could go completely flat for the bins in my fridge and such. The old GE rack will fit the KA, but the KA has ball bearing glides in the way that would have to be removed. the 1-2% of the time I will miss the old GE 30 minute cycle is for my holiday prep. I toss all my china and crystal in the DW to freshen it up prior to having guests over, could b problematic at 60 minutes.
Energy wise the KA sips power. I have a SmartThings setup with a readout of actual current use and it really uses very little power. Plus at 39db it almost silent running, I may hear a bit of water sloshing about but I have to listen hard to hear it. One other quibble is I'm not a fan of the dark interior that stainless unints have, would love some lighting in it, miss my old GE with the white interior.
all in all to the OP I'd say go new, save energy and water and get used to the longer run times, I don't see much of a down side. No need to search for NLA parts for an older unit.
