OK, dwarfpool's at about 1 MAX every 5 hours too. So I guess it isn't your pool's fault, just the whole MAX mining world is getting more crowded and slower.
I'll crank the 290X up to full speed and point the whole 605 Mh/s at maxus.net2pools for 24 hours and see how I do.
You need to pick a pool and stick with it for a few hours (days preferably) before you judge the payouts.
You have to understand that you only get coins when a block is found by the pool. here's an example....
A pool takes on average 1 hour per round and you have 10% of the hash power. Every time a block is found you get 10 percent of the block - in MAX case 9.6MAX. Therefor you SHOULD be earning 9.6 per hour on average.
Now, if that pool gets lucky and finds a block in 50% of the time (30 minutes) you will get 9.6 in 30 minutes so your on track for 18.2 per hour.
Then there;s the unlucky (like when you jumped back to us) where you hit a 200%+ round. so you would only get 9.6MAX in 2 hours.
follow?
Finally there's how long you are in the round. If you are in the round at the beginning you will get your FULL 10% share of the reward. If you join half way through though, you will only get 5% as the other miners have already done half the work.
The good luck/bad luck should average out over time but if you pool hop every few minutes, you'll never get a full round and your payouts will vary wildly.
Give a pool 24 hours or look at the "blocks" page - to see the over all luck.
Hope that helps.
Nut
make me sad 
