An experience of @s9tim shared.
Printer technology and material:
Resin is pretty good but has its drawbacks. The resin comes out smooth as you said and does not have layer issues. However, most resin is brittle and would crack randomly.
I had some resin props printed the same way with the same resin last 20 sessions and some last 20 minutes. There was no consistency. I have found the tougher resins that cost more do not break but they flex to much and the prop vibrates. It seems to make the resin more durable and less brittle the resin is softer.
I have printed about 15 types of resins and 10 or so fdm filaments including CF varieties and plain polycarbonate has been the best I have found for printing prop blades. I have some that have lasted over 50 hours of run time. They generally don’t break unless you hit an object in the water.