Traditionally we performed code review before commit, I had an argument with my colleague today, who preferred code review after commit.

First, here's some background,

1. we got some experienced developers and we also got new hires with almost zero programming practice.
2. we'd like to perform fast and short iterations to release our product.
3. we all team members locate at same site.

The advantages of code review before commit I've learned,

1. mentor new hires
2. try to prevent errors, failures, bad designs in early developing cycle
3. learn from others
4. knowledge backup if someone quits

But I also got some bad experience, like

1. low efficiency, some changes may be reviewed over days
2. hard to balance speed and quality, especially for newbies
3. some guy felt distrust

As to post-review, I just knew little about this, but the most thing I worried about is the risk of losing control, people never review.
Any opinions?