I have both a bolt and SB. The bolt was dead on arrival though so I didn't get to
vape with it at all. Tore it apart and the super thin wire was broken off the positive battery contact. The switch is a plastic horn switch like you find on box
mods or from
madvapes.
Compared to the the silver bullet its very light weight and a good bit smaller even with 18650 extension ring. I did noalox the threads and it doesn't feel as good as threading the silver bullet. Also it doesn't seem like the battery fits as well in the bolt, most like due to it being an 18500 tube with an extension.
All in all, the only comparison I can make is with build quality, since I didn't get to use the bolt as it was doa. The best example off the top of my head is that the bolt is a port-a-john and the silver bullet is a brick s---house. It feels like I could toss my SB off a building and vape it on the side walk. The bolt, not so much. I've read that some people are very happy with them, but for the extra couple bucks, I'd take the SB any day.