The Thunderheads fly great for me. Think I'll order the replacement blades and use those even though they're 85gr!
I'll pound this again, just because your bow is not as fast as the new monster FPS bow it doesn't mean that you have to shoot lighter. Why do you think that guys that shoot Trad shoot 600+ gain arrows, KE! 14 Years ago the bows started shooting over 300 FPS we were all killing deer with those slower bows.
I've always preferred K.E. over speed. My Trad bows my arrows are over 650 gn, my compounds I shoot 643gn using 220gn Muzzy Phantoms with bleeder blades which gives me 21% FOC. That gives me bone breaking power, I've knocked deer down, and I don't have a monster speed demon bow. I don't know how fast they are, and I really don't care! I know that faster means flatter trajectory, and will compensate for poor distance judgment.. and we all know what that means.
Little brother you'd be fine shooting 100gn thunderheads if you like that broad head 15 more gn's is not going to make that much difference, just add a little more K.E. to your arrow.