I've had a CPL ever since MI became a "shall issue" state back ~ 2001. I got mine primarily so that I could legally wear a shoulder holster under my hunting coat for rifle deer hunting season. Also, the ability to purchase a handgun w/o obtaining a purchase permit in advance from the local PD is another big plus.
However, there are certainly downsides. You are accepting all liability for the use or brandishing of that weapon, intentional or not. You're potentially opening yourself up to felonies that you wouldn't be without it, as well as potential complications when interacting with police on otherwise mundane things (e.g. traffic stop). It's your responsibility to know where you cannot go with it. It's your liability, or inconvenience, if you need to go somewhere that you can't with it -- either leaving it in your car parked off-site, or just not going there period. You also need to be aware of private property rules, such as your employer's, and knowing what their rules are. Most big companies do not look favorably on their employees bringing weapons to work - as in cause for termination if discovered. And if you're not a fan of Big Brother, then you may not want to register all of your fingerprints with the PD/FBI, as well as getting formally registered & documented as CPL holder.
Obviously, all that is worth the liability/hassle if it saves you or your loved one's life. But don't kid yourself that there's no downsides.
