Not sure why 302 was used instead of a 301, as normally a 301 is used as a redirect and the effect would be much better as it's telling the SE that you've moved/changed your location online. If 301 is possible, then by all means use the 301.
Previously, the 301 links do provide enough link juice to your site - in the wee days of the 301 redirect method. Can you imagine having a PR8-9 redirecting site having their sub-link or sub-domain pointing back to your site - it definitely trickled in the link juice, and when done in bulk, it gave some good link juice in the process.
Power those redirect links with some article links from behind, and it should get those 301s noticed in the process, immediately.