Hello and welcome to the forum.....In my honest opinion, I would say for a few hundred dollars more than the psr 1500, I would go for the PSR 3000 and I'm sure you could buy one for around $1,500 US,....they
are a very professional K/B that comes with
great piano sounds thast you ask for as well as many other professional sounds and the in and outputs are what you ask for plus the weight is only about 11 kilos...I think this is the K/B for you from my point of view
I can't say anything about the Korg or Roland
you will have to wait for other input on them
good luck...
Tony Rome