Yes, I’ve had my X1600 mixer since early last year.
Highly. I took mine over to a friend’s house, he’s been using Trakto Pro for over two years, and I literally had to pry my mixer out of his hands. He liked it that much. He later went out and purchased his own when he realized I wasn’t going to let him use mine.
The 1600 mixer trumps the 1500 in every way. Especially in sound quality I won’t list the features here as I’m sure you’ve reviewed them already. But I will say that the Flex-Fader can be adjusted in place. No need to remove it like on the 1500.
With the 1600 you have 4 Midi Page/Function buttons as well as 4 Parameter knobs that can be mapped.
I don’t have any experience w/ the 1600, but I have always been fond of denon products. I have had the 900 for awhile, in addition to various other denon products, w/ no complaints. I say go 4 it.