I have a built in unit by Progressive, and I like it. As far as the question as to if you really need it, think of it as insurance. We do 90% of our camping in the summer months and the chance of thunder storms is likely, at least once during a normal week. It will not protect you from a extremely close lightning strike, but it will filter the surges and spikes that are on the line during the storms. They are not absolutely necessary, but really nice to have.