How good are JDM cams

I am thinking about buying JDM type R cams for my 99si. I was wondering what kind of gains could be expected by putting them in as well as port and polishing my head.

If your talking about ctr cams...yes they are good as hell. U can really feel the difference on top end!! My friend had it on his b16 rex and it made a big difference! I don't know about port n polish head though?