If you are used to shooting 2 3/4" dove loads, a 3" turkey load will get your attention. If you've ever shot 2 3/4" slugs, you can handle a 3" turkey load. And if you feel the need for the 3 1/2" shells... well... up your life insurance ahead of time! LOL
I've shot many 3 1/2" shells, and they won't kill you. I'm used to a shotgun, so 3" shells don't even phase me. (after a patterning session I can tell I've been shooting though) Your first one will surprise you. Just keep the gun in the meat of your shoulder and keep your cheek down. And WEAR HEARING PROTECTION! Guns don't kick nearly as bad when you can't hear them.
rw