Results
So ....... It held up better than either of us hoped for!
We only destroyed 4 of the plywood targets (had several spares along just in case) & also the support plank. The side pieces survived for another trip!
Started with the 9mm's, then moved up to the .45's & also the 'scary black rifle'. Had a great time using the shot timer app on Mr. Chickadee's phone to see how fast we could knock down all 4 targets.
Mr. Chickadee's best: 4:84 in 5 shots with his Springfield TRP

My best: 5:25 in 4 shots with my Sig P226
We also shot some other targets - most notably was an old crappy dental machine from my practice & also a 'retired' hard drive.
Ammo count:
200 rounds reloaded .45
150 rounds FM 9mm
150 rounds FM .223
approx 80 rounds various HP in .45