A few months ago at my local range, I saw a gentlemen using one.

He loved it. But.....

He said if you mistune, you really mess up your arrow. In other words, it will tare the fletching and sometimes the nock right off the shaft.

Other than that, like typical full capture/drop away rests, you gotta watch those screws. If they come loose at the wrong time....good luck finding those in the leaves of your trail to/from your deer stand.