1st looks nice but a bit grainy
2nd looks great, but the grain is also quite large, and the rim material looks a little dull
3rd I like this one, but the background lets it down a little imo
4th looks great!
5th even better! but the rims look a little dull again
6th looks brilliant! my favourite, great job
All of them are really good, just some small tweaks will make them a lot better i think
Keep it up!