For my laser etch 'n' fill projects I started with some really old system-3 using the 207 hardener I had on the shelf.
This hardener was the low viscosity stuff since at the time i bought it I needed it to flow.

That worked well for fills with colored mica mixed in, but I ran out. Gawd awfully expensive stuff. I needed a few more fills and used regular 15 minute epoxy and that also worked well.

I had never used any acrylic resins before and jumped on a product Nathan posted.


What you get is 1 quart of stuff (mixed).

I doubt either epoxy or this stuff will avoid scratches on a cutting board, but long story short, I love this stuff!

Cost is very low ($15 for the kit with some mixing cups and proctologist finger tool covers).

With the epoxy it dried as expected. This stuff has a lower viscosity and really flowed out well. I was using it at about 65 degrees and the working time was 1 hour+ before any signs of stiffening. This was a bonus in that I had plenty of time to manipulated it as I needed. I used separate 5cc syringes to pull equal amounts out of the bottles since the droppers provided in the kit suck. Been using the same pair of syringes (marked A and B to avoid any cross contamination) for many pours since the stuff doesn't seem to kill them chemically.
 
After the pour, I put the project into my shop ex-food dehydrator at 85 degrees over night.

Cure times were in agreement with the specs. By morning, (16 hours) it was hard but could still be slightly dented with a firm fingernail push. After another 24 hours in the house it was as hard as any epoxy I've used.

Since it took about 4 hours in the dehydrator to stiffen enough to not flow, any bubbles introduced had floated out and popped. 

Since the viscosity is so low, it soaked into the wood a small amount which I'm sure gave it a kung-fu grip and will not fall out. 
My etchings were from 1mm to 1/4" deep and all worked out well. I like the deeper pours just because that gives me extra material for drum sanding, etc. without worry about blowing through the layer.