I've shot spitfires for 15 years. I've yet to lose a deer because of lack of penetration (the few I've lost would've been lost with any head). Having said that, I just don't think the law of averages is on my side. I have had blades break off. I spent a lot of time shooting this year, and took the time to tune my bow. Nock tuning, broadhead tuning, all of that got me all dialed in with fixed blades. The main reason for shooting mechs has gone away for me. The first two deer I shot were with a muzzy three blade, and both had plenty good blood trails. Obviously if I had blade retention and double lunged them with the spitfire's, I had great blood trails most times. There were a handful with a high entry/exit that didn't go great.
I have two arrow setups I'll be shooting this year - 200grain IW's with 50 grain insert, and 125 grain exodus with 100 grain insert. If I get a chance to run out west for a little bigger game, I can swap the IW's to the arrow with the 100 grain insert to get arrow weight up. The 100 grain inserts give me broadhead flexibility and maintain the FOC.
High FOC arrows are flying like darts.
To answer your question, yes you've got enough juice to get an expandable through whitetails in many situations. But the situation is always dynamic, and there are a lot of variables that will leave you disappointed. Many many advantages to them depending on your style of hunting, distance you shoot, amount you practice, amount of time spent tinkering with your gear, etc.
For me, I am just getting more averse to risk of things going wrong as I get older. My tracking skills have improved, and we have dogs a phone call away to track a dead deer, so what appears on average to be less obvious blood trails aren't as big of a deal to me.