Yep.
Have one.
Used it on a 6x45mm AR barrel that seemed easier to finish-ream while installed, rather than off the receiver; after fighting with the manufacturer for over a year (3rd [4th?] barrel with short headspace).
Worked just fine.
Keep it well-oiled, or it will rust like a sum-B.
Based on the project rifle lineup, I'll probably need the tool soon to finish a .307 Win chamber, and a 7x57mm chamber, as well. (I really need to stop putting rifles together from left-over parts, free barrels, and 'grab-bags'.
)