It is not a "Must Buy" although since I play both games I did purchase the program. It works just as well as the Hold'em version. However, there have been no other auto rate rules developed for Omaha PT other than the default, which is a problem.
So, when I go to auto rate players I only have it rate players in LIMIT Omaha H/L games with players greater than or equal to 7. If you use the rules for anything else [PL/NL Omaha High or H/L, or Short Handed (any Omaha game), etc.] it will be inaccurate.