Matty,
I found it is well worth while persevering with the 3x but I obviously have the time to do it.
The tyros would be a good choice if you can't overcome the difficulties with the korg.
I originally had to choose between the korg and an audya 5 and it was the price that swayed me plus problem reports on sites about the audya.
I'm sure the ketron is a good keyboard but it would have to have gold keys to beat the Korg. I also have a yammie 710 which I play when I just want to plat. Maybe you could keep the korg and get a double stand and a cheaper or 2nd hand KB that is easier to work. That way you can take your time learning the korg.
I do like a challenge.
baz