I went with Bosch Cobalt bits rather than that set above :

https://www.amazon.com/Bosch-CO2144-4-1-Cobalt-Drill/dp/B000AESUFS/ref=sr_1_3?keywords=bosch+cobalt+17%2F64&qid=1572282359&sr=8-3

I think these should work better, have one for my pilot hole (17/64) and one for my larger hole 27/64 Also got a 13/32 for the last baffles and will probably use it on the endcap as well.