And if you want a hilly 600k tune-up before PBP (or a last-minute qualifier), the NER one is the very last weekend of qualifying and is like 20-21k feet of climbing. It's flatter than the old NER one by about 1000 feet, but that's not saying that much. I'm planning to do it but not as my PBP-qualifying 600k, because I do not expect to be able to sleep on it and finish under the limit, so it will be an adventure. I've ridden a lot of the course on various rides and it's beautiful.
The Central NY one was my first 600k this year and it has 13k feet climbing -- a bunch of rollers (especially at the start and finish), two big gentle climbs barely steeper than a false flat, and some big swoopy downhills. And great pavement for almost all of it, which was a pleasant change from New England. Really nice route, definitely recommended for something not too hard, though it probably doesn't line up with my schedule this year.