noise gate

[<Randy.Lilleston@xxxxxxxxxxxxxxxxxxxxxxxx>]

 Folks -
 'Twas trying out some amps the other day at a music store
and was having the usual feedback blues. A salesman who said
he knew some harp players suggested I invest in a noise
gate. He said it would kill the feedback - that I could wave
the mic in front of the amp without the usual results. Does
anyone have any experience with this? Am I being fed BS?
Will this affect the slightly distorted tone I prefer?

-Randy-