I figured the GTA organizers created this category to pull the match AP guns separate from the sportsters like the P3.
I asked that question in reverse on the co2 pistol group. Because, if I could shoot my match co2 pistol in their match, a match pistol would have an advantage over a sportster pistol. They said yes, so I did.
So if anyone wants to shoot a sportster pistol in a match pistol match, that would be OK, but they would be at a disadvantage from the point of the mechanics of the gun.
re - pistol
Your IZH-46 IS a match pistol. SSP is simply the powerplant.
re - grip
Since it is a match pistol category, I would say we "try" to align to standard match rules, so initially I would say one-hand grip.
BUT, to not exclude people, if you shoot 2-hand, then just state so in the post. That way I will know why you beat me :-)
re - sights
I'm open on sights, as even at the national level, I've seen discussions on allowing red-dot sights.
And as some of use (like me) get older, it gets harder to see the front sight and target. I'm using open sights as long as I can, cuz I'm in denial of my bad vision. :-)