I recently purchased a Site Lite SL-100 to boresight my pistols and rifles with iron sights, red dot sights and scopes. This system is much more accurate than the typical made in China laser bore sighters that are inserted in the chamber. It also works with sights with no magnification. With the high cost of ammo, it was easy to recoup the $100 it cost me, not to mention the time and effort I saved.
Some things I really like about it;
Well made and finished in the USA. This is not a disposable tool, it's a keeper
Comes with everything you need.
Excellent documentation and software and tech support.
The laser is bright enough to see at 25' in the bright Texas sun.
The batteries last more than 5 mins.
Easy to use, short learning curve. I was on paper with the first live rounds.
Comes with a hard plastic case that hold all of the parts and documentation. Has adapters to fit .22 caliber to 12 gauge in the box.
I used the SL-100 successfully to align the sights my 7.62 X 39 CZ-527 with an Aimpoint red dot sight, Ruger Mark II .22 cal pistol with an ER scope, a couple of Ruger 10/22's with scopes, 12 ga Mossberg 500 shotgun with a laser sight, SIG 228 with new iron sights and a Browning .308 BAR with a scope. I also tried it with an AR-15 with a scope at the range.
http://sitelite-lasers.com/product_SL100.html