We are looking to purchase some Catalyst Antennas, we are outside of the VRSNow region so we will be connecting to the State VRS networks. What real life accuracy levels can we expect to achieve using this method with a precision subscription. If we are only using a decimeter subscription and VRS will it limit the accuracy to decimeter level or will it be at the accuracy of the VRS network?
I'll start with the second part of the question - yes, the decimeter subscription will limit the accuracy of the State VRS network to 10cm.
So it will converge with the default VRS performance down until it hits the 10cm threshold, then essentially stay there.
In other words the subscriptions are decoupled from the correction data mechanism - doesn't matter if you use VRSNow, a custom NTRIP or even RTX.
Regarding the overall accuracy: with a Precision subscription you get whatever the VRS network plus your surroundings provide. So ideally its between 1 and 2cm horizontally; with moderate sky view you end up in the 3- 4cm ballpark. But it really depends on the area and open-sky availability you work in - so best thing would be doing a quick test run at a 'default' location to verify my guess if this is possible.