Here's an Impact compared to an Accura, sorry no Optima to compare. The Optima would be a half inch shorter than the Accura. The measured length of pull on the Accura is spot-on at 14.5", the Impact is longer than advertised, it measures 13.75" with the hammer cocked and the 1" spacer installed. The Impact is topped with a Nikon Omega with 5" of eye relief, a one piece base and Warne rings. The Accura has a Nikon ProStaff with 3.6" of eye relief and the supplied one piece base/ring combo from CVA.

I don't care for the supplied one piece base/ring combo, I prefer a one piece base with Warne steel rings like on the Impact in the photo but I'm not sure if you would gain any adjustment by going that route on the CVA. The Impact is a good shooting rife, the sliding hood design is ok, it works, but I like the lever on the trigger guard better. I did shim the barrel to action fit on the Impact, it was a little wobbly from the factory. The weathershield on the Impact barrel is holding up well, I wouldn't get a blued muzzleloader from TC, they always seem to have rust on them in the stores.

If your Optima is shooting good at the range, I don't think you will gain anything from the Impact accuracy wise, but you will get a shorter LOP, not much, but a little shorter than buying a youth CVA buttstock.