Security System Plan

Fixed is probably fine unless you were going to get a higher end unit that also did phone and cable, then replaceable modules would probably be nice. My preference is to check with utility on the meter mounted ones first. See if they will install one you buy or if they sell or lease them. If the lease price is reasonable that is a good option because it is direct connect and they are responsible for maintaing/replacing it if needed.
I'll give fixed a try. I buy at wholesale so worst case scenario I have to buy another one. Thanks.