Upgrade to e5200 from e4300 on Asus P5B?

i was wondering if it would be worth the upgrade to get a intel e5200? i have a e4300 on a normal asus P5B board but its hard to overclock past past 333mhz because of the motherboard so i run at about 3ghz....would it be worth the upgrade to get the e5200? and just overclock that? or would i have a hard time overclocking it? i have ddr2 667 memory so im limited to 333mhz fsb bus anyways. also, what would be the overall performance increase? if its not worth it than ill just wait and get the newer 1366 socket later this year or next