I manage a gorup of trainers who travel from city to city doing presentations.

Now, it's easy enough to present to a group of 20-30 poeple without a microphone, but it does get tiring.

I'm looking for a portable, wireless microphone/amplifier/speaker system that my trainers could use in a room that accomodates up to 50 people or so.

My goals are to make it easier for those in back to hear everything, and to reduce speaker fatigue when the presenter has to conduct multiple sessions throughout a day.

I'd also like to use it at trade shows for 1 to 1 or 1 to few dicusssions so my trainers don't need to speak loudly for 10 hours a day just to be heard over the white noise of a show floor.

The mike has to be wireless, and the system had to be protable and durable enough to survive jumping around to different cities and stand up to baggage handling.

Has anyone used such a system, or is there one you might recomend? What features should I look for in such a system?

Thanks,
Cromely.