We do and it saves times and money, pays for itself quickly.
I keep one in my pack to check my zero in the field. The back of our business cards have a "zero check" target so you can easily verify that your scope is still zeroed in the field without shooting it.
Here is how it works.
1. Sight in rifle.
2. Install boresighter
3. Make notation of crosshair location in boresighter on card
5. Keep card with firearm and boresighter
If you drop your rifle or wonder what the airline did to it, you simply put the boresighter on and make sure it is hitting the same spot you noted on the card. If it is off, you will know it before you shoot it.
We built a web page to help explain it a little better.
Every order we ship includes a card.