Right, neither will pass all PageRank either. But the 301 is definitely the most commonly used and recommended by Google (as long as you can't preserve the exact same URL).
302 is a temporary redirect. As such, Google and the other engines will NOT transfer credit for inbound links to the redirected URL over to the target of the redirect because you're telling them it's only temporary. It's going to change again later. 301 is a permanent redirect. As such, Google and the other engiens WILL transfer credit for all inbound links to the redirected URL over to the target of the redirect because you're telling them it's permanent. Yes... there is "some" PR loss as a result of the 301 redirect. You might lose 10-15% of the original redirected page's PR, but retaining 85-90% of the old page's PR is better than losing it all. The loss is due to the damping factor in the PR calculation since a redirected page is essentially a page with 1 outbound link. There is a decay factor or damping factor that causes a little PR to be lost with each link.