The difference I see is the shape of the hole. Thom Thumb only comes in prefab round holes sizes, at least on the web site. I use a milled thumb, my thumb is very flat. Switch Grip lets me mill my thumb just like I would into a slug, because you are drilling into a slug.
I like the stopper on the Switch Grip, same depth every time. Tom's Thumb tells you to drill 3 1/4 inches, but a 1/16th difference in depth is a big difference. Need a stopper system. Too much volume in my shop to take 30 minutes just to drill the thumb hole. Now when I get a 2nd press..........!!!
Switch Grip is lightening fast. I use tape just like I always have, my thumbs feel great.
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Mike Austin's Precision Pro Shop
Houston, TX
Drilling and Tech Advice BirdDogbowling.com
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