"I'm curious, if the data I'm sending with the old version is spot on with CWOP, why would I upgrade?"
Steve,
I can't answer your question, but I think I can enlighten the situation somewhat. This is reasoned opinion and not known fact. Ambient is one of the largest sellers of Davis Weather Stations. Ambient is also the author of one of the two largest weather software programs. CWOP has created a market for themselves by soliciting owners of personal weather stations to give them free weather reports from locations around the world. CWOP pays for this data with quality feedback in the form of the beloved Green Check or dreaded Red X. Where does CWOP get the STANDARD data they test your data against? They won't tell us but I would bet that, in the case of pressure, it is obtained automatically from airports. Being obtained automatically from airports means it is Altimeter Pressure rather than Meteorological Sea Level Pressure which WAS all that Davis PWS reported. There was a large discrepancy ,especially at higher elevations, between SLP that Davis reported and Altimeter pressure that CWOP required (Note that WD, Cumulus, and VPLive have sent the proper format for years). After years of fighting, with Ambient refusing to send pressure to CWOP in the form they needed, this latest upgrade does that. However, there have been two major happenings in the meantime; one, the Ambient forum was dissolved over this issue and two, Davis added the ability for its stations to provide the pressure data in the format CWOP required. So now, since your elevation is approximately 1000 feet, if you want your station to display the barometric pressure to correspond to the local TV station, and also send info to CWOP in their format, you should upgrade your software and change your Davis hardware to SLP.
FWIW ( a lot of opinion and some facts thrown in )
George