I made just the same experience, Michael. In the last two years I used ADG419 very much for a certain project, because of it's superior performance.
Two years ago, I had a lot of discussion with people from analog devices, because some specifications deviated from some older datasheet. Then, they told me, that they have changed fabrication process in the meantime.
It's my experience, that parts of MAXIM are often superior to other manufacturers.

Bye,
Kai