I have only played the older two rocker pedal models so I'm not up on these. How does the EX compare to The Line6 HD models or the Zoom G3? Are Vox amp sims still holding their own or are they due for a makeover?
Korg haven't bothered to update the REMS software probably because the AX3000G didn't sell so well so they haven't updated it, and also because of the economic climate in the west where where they expect to sell a large proportion of units. That said there's nothing wrong with the Korg/Vox products they still sound ok and have lots of effects and models, but if you want more flexibility then there are better options out there for the price range you looking at. The Zoom G5 looks like a very nice product in your price range when it hits the shelves and the HD300 may well be worth a look too. I had an HD500 and found the modelling to be very impressive but the interface to be frustrating.The effects for the most part were very good and it's excellent for recording. I'd expect the HD300 to be excellent value for money.
Just to add, I still use an AX3000G and it still sounds pretty good in most areas and it has alot less features than the newer Vox equipment. Some of the hardware on the Vox equipment will be more modern so that have should have some impact on the sound.
I switched from Tonelab to HD series... totally different.
I prefer HD...