I am considering a Fender Amp, but I hear on the net various opinions. Do you really need a 100 watt amp or does a 40 watt give you more than enough for any venue? Understand we are talking about the AMP for a single guitar player and NOT the PA system used by a band. I am considring the Fender Mustang 40, but I also like the Fender Champion 100. Your thoughts? Thanks