Our POI says there are new Ops Spec coming out for RNAV. Specifically mentioned was the Type A & B SIDs and STARS and Q routes. I've been trying to brush up on AC 90-100. I also have the service letter from Universal which lists FMS units that conform to AC 90-100. We fly with a UNS-1M (GPS) and are filed /G. It never had a published RNP value. How do you determine the RNP for older units or can you? Basically I see that if your unit - 1) doesn't meet the AC 90-100 parameters, and/or 2) doesn't have pre-loaded SIDS and STARS, Q Routes from the database, you can't use those type of procedures. We still should retain normal enroute, terminal, and approach operations with GPS. Correct? ATC has issued RNAV STARS to us before and had to explain that we couldn't accept it due to our equipment and got re-cleared via a standard STAR. They questioned - "you are a /G, correct?", I said yes, but our older unit does meet the new parameters for Type A or B. I wasn't going to spend much more radio time than that. Anyone else on speed with this?