I started with the cheap 3/8 ones and broke a bunch of the heads. Figured out I was going too fast. Got a Blair 3/8" and it works better, but you need a good center punch or partial drilled hole to keep it centered.
Then started using this 5/16" one that is like an end mill with a center tit. Nearly self centering, requires a little more pressure but cuts really well and I appreciate the smaller hole on the panels I will reuse. I use all of them, depending on what I am removing.
https://www.amazon.com/gp/product/B005TY5EPI/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1The Lisle spot weld chisel is worth the investment too
https://www.amazon.com/gp/product/B000BQXBJK/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&th=1
