My subbie and I have been playing with an electro probe recently and W/we both love it. The one I have was cheap bought at our local pitiful excuse for a sex toy store, since we both enjoyed it so much Id really like to get a tens unit. Im all new to electrical play as is my subbie. Can anyone offer some advice on buying a unit? Theres so many to choose from Im not really sure where to start. As well as any tips or tricks I should know before we get one. Thanks A/all.