Your question is an interesting one because the three instruments you ask about have three totaly different ways of storing and playing styles. The easiest one to explain is the Solton X1 because there are 200 memory locations for your own custom patterns. There is another 200 locations for you to edit sounds, volumes, effects, etc. called custom styles. In the solton world, a pattern is a user programed style and a style is a factory programed style.
The korg is different because you can have I believe either 16 or 32 custom styles which then can be used in an arrangement. Arrangements consist of a style, either stock or custom and all sounds and effects and tempos used within this arrangement. In the i30 you can have 128 custom arrangements but remember you can only have 16 or 32 (i can't remember when I'm at home and not in my store to give you the exact number) custom styles within these 128 arrangements.
The Roland uses a completely different system. There are 16 locations where you can store your custom styles you've made, but, there is only one location (the last one) where you actually make your custom style. The concept with the roland EM2000 and G1000 is that after you have made your custom style, you can save it to a floppy disk or a zip disk, and you can instantly recall a custom style without saving it in your internal memory. This way you can have hundreds of custom styles at your fingertips. What is actually happening here is that every time you call up a new custom style in the disk link mode, you are actually calling it up into the one empty location temporarily. As soon as you call up another style, it is overriding the previous one. All three of these are very different but I think the Solton and the Roland are better than the Korg because you have the ability of playing many more user styles at a quick change.
George Kaye
Kaye's Music Scene
Reseda, Ca.