Hello: I would appreciate any help with FM transmitters. One maker only sells one watt transmitters with 5-10-20-30 watt "amplifiers". This means there are two separate units. Is this equally as good as the FM transmitters that come in a one piece/cabinet? Are there different ways of propagating FM transmissions? Is the one watt with amplifier the best way? Thank you for any light you may shed on the subject.