Hey Chris. If you really want accuracy I think it might be good for you to wait a bit. I don't want to give too much away right now as I feel that the more I talk about it the more questions I will have to answer on the topic and then if I talk to mush about it many customers will be frustrated that it's not available yet and it's not in stock yet. So it's a bit of a catch 22.
With that said we are working on a new mini gauge that will go from 0-100psi and have 1% accuracy so this will be the most accurate gauge and will fit into all these products:
Blowtie Spunding Valve
Inline Regulator
Mini Core 360 Regulator
RAPT Fermentation Chamber
... and several other products that will be available in the future.
We will be able to sell this at about $9-13.
If you talk to any credible gauge manufacturer they will tell you that when you go below 100mm diameter gauges you really start to sacrifice accuracy as it's very difficult to make a bourdon tube accurate that is very compact. As "mini" keg systems become more popular and everyone likes things to be as compact as possible we believe we have to make new mini digital pressure gauges that use electronics rather than analogue bourdon tube. So the wheels are in motion with regards to this but you will have to wait a few months before this is complete. I cannot give a finish date for this as we are only at the early stages of development.