In my mind, they are two very different animals because you are not just hunting the good hands, you are indeed hunting those low hands but obviously, not in both types of games.
I think the best learning ground is going to be Omaha without the Hi/Lo and pot limit, if you can get it.
In my personal opinion (and I really mean "my" opinion, not some other websites opinion) the order of Hard to Easy in Omaha is as follows:
Hard Omaha Pot Limit
Omaha Hi /Lo Pot Limit
Easy Omaha Hi /Lo NL
If there are any Omaha experts reading this, please correct me if I am wrong in my thoughts.
I put them in that order because that's the order that I "feel" when I play Omaha (which isn't that often).
Let me know your thoughts Katt.