Although I am a big fan of UVM Pro, and it is the mapper I use most often, it does not have "unwrapping" or "relaxing" capabilities as the other two products do have. I do my unwrapping and relaxing manually in UVM pro, and I think I get better results than the automated ones, BUT it takes a LOT of time to do it. My advice, if you are new to UV Mapping in general, stick with UVMapper - the others will make your eyes glaze over with techno-jargon and very user-UNfriendly interfaces.