Have you ever raised someones bet thinking you had the nuts just to find out you didn't see the flush. These types of things happen to some when they play a lot of tables at once.The 4color deck will fix this. It may take awhile to get use to it. But once you do problem solved.
I like it personally. Especially if you're playing multiple tables at once. I've missed flushes without it. I will say that when I go back to the casino and play though sometimes my brain wants to see blue diamonds and green clubs. Very weird when they are red and black lol
I don't know if it is defaulted on some sites. I tend to use whatever it is without changing the deck. If it is not I have not experimented with it yet to see if it would be useful or not.