I use North Sonic II hearing protectors. I am left handed so I use one in my right ear. My rational is the my left ear is directly behind the gun and somewhat protected from muzzle blast. Must sorta work, the last time I had my hearing checked, my hearing was within an acceptable range for someone my age (my wife still thinks I am hard of hearing).
I have found that many times I hear the pigs before I see them. I do think it is important to take some steps to protect your hearing.
First off the only dumb question is one left unasked! And second yes it is a good idea to use hearing protection in the field. Especially in your "gun ear" . If you are right handed then its best to put it in your left ear as it is the one that will collect the most sound from the muzzle blast. I wish I had realized this at a much younger age as I have lost about 30% or more hearing in my left ear. The Walkers Game Ear is a good example. You will have an increase in hearing in the field and the sound suppression works great during a muzzle blast situation. There are many to choose from and most all work about the same...You Have electronics and then you have "valved" suppression...The "valved" ones work by staying open during regular decible levels allowing 95% or more of natural sound in and then during an increase in decible pressure it closes up suppressing it..They work pretty well and much cheaper but I personally like the electronic ones since they increase your hearing range greatly.
As a Taxidermist I look at hundreds of Whitetail Bucks every year. I know that I have seen many different ways people judge the size of racks on live deer. I think for the most part they all are pretty close. I'm going to give you some measurements that I have noticed being right on in just about every deer. We have used it in the last couple years and have only been off by about 5-6 inches. We do study the deer while bowhunting so we get a little more time to look at them....