Need some help understanding modern arrows and broadheads.
 

Hey guys,
I'm just getting back into bow hunting since I switched over to muzzle loading in the early 90's. So I went in a few years ago and upgraded all my archery equipment. New bow, carbon arrows the whole deal. (I hunt mule deer and elk)The one thing that I never changed when I upgraded was my broadheads. For all my past hunting I have always used the same heads, the muzzy 3 blade 125's. I have even used them to take deer, elk over the past few years with my new set up. So the other day I go into the archery shop and the "archery pro" all but refuses to sell me the broadheads. He tells me that I should not be shooting a head that heavy with the new "high speed equipment". He then tells me that fixed blades are pretty much "out dated". So I just wanted to throw it out there to all you guys in hope to get some info./advice on this. Why can't you shoot the 125gr heads with the "modern equipment"? And are mechanical heads of today really "superior" to fixed blades? They seem to shoot just fine out of my setup, is there a legit reason to switch to the 100gr version if I stay with the fixed blade? I am definitely no archery pro. and I am way behind the times and out of the loop I guess, so any info. and or advice on this that anyone is willing to share would be great. Thanks everyone in advance.

Go to a different pro shop he is full of $hit
I wound't give him any more of my money

MN is right although I wouldn't have been that blunt. If your arrow spine is heavy enough to handle the 125 grain broadheads and the fly true for you there is no reason to switch. A 100 gr BH will probably only give you about 5 fps more speed (if that). But it will definately give you more penetration. Which is a plus for elk.
As for the Muzzy 125s I also used them for years but today there are better heads out there. One of the best flxed blades are the Slick Trick line of broadheads. Muzzy Phantoms are also a good choice.
The mechanicals today are better than the earlier ones being more reliable. But nothing, and I mean nothing beats a good flying fixed blade.

Not too hard to see what the pro-shop is doing, when you look at the price tags of the items they recommend versus the items they don't recommend.

My Cabela's brand FX-3s kill deer just fine. Same with Muzzys. The only way they won't continue to do so is if deer evolve to grow an armored shell around their vitals.

Also, many shops don't want to take the time to assist guys in tuning for good broadhead flight, and many guys can't do it themselves. The Magic Answer is "modern" mechanical heads.