As already said you can spend 100 credits to get Refreash, Regen, or increased food duration (2X the length I've been finding on my sushi.) Those effects last in any area though as I've been informed. Never had much chance to test it out due to lack of any exp parties outside ToA areas on my server now a days. >.>

Also while inside ToA areas it gives you a small exp bonus on mobs. Although I've never really noticed a huge difference in the exp bonus. <.<