The BeachTek adaptor (or similar) is the best investment you can make. I wouldn't worry about the difference between the two mics. I have the less expensive one and it has worked out fine for me. As far as where to get both of these products, most any discounter will do. There's not going to be much difference in price regardless of where you buy. If one place is cheaper, then they proabably make up for it in a "handling charge." B&H has fair pricing.