If you're not afraid of a little math, you can figure out your expected payout pretty easily.  A true PPS-based pool assigns a value in BTC to every share, which is derived from the current network difficulty and the block reward.  As of right now, the difficulty is 40640955016, and the reward is 25BTC.  So, we can derive that each share is worth 25/40640955016, which is 0.00000000061514BTC per share.

That's all well and good, but how do you figure out how many shares your rig expects to submit in a day?  Another formula will get you that value:

Difficulty * 2^32 / hash rate / 86400 = expected time to solve a block in days.  For a 1 TH/s miner, that value is 2020.27 days.  Number of shares, divided by number of days = expected shares per day.  That same 1TH/s miner expects to find 20116567.61 difficulty 1 shares a day.  Take that and multiply it by the value of a share and you get expected earnings on a PPS pool per day.  The 1TH/s miner expects to get 0.01237451BTC a day.

Since our friends at Discus Fish charge 4% for PPS mining, you would get 96% of expectations, which is 0.011879523BTC.

You can change those numbers to fit whatever hashing power you have to determine what your expectations would be.

Hope this helps.

Edit:

Here's the formula all nice and prettied up for you to calculate expected earnings on discus fish.

Of course, if you're feeling really lazy, go to an online calculator like https://bitcoinwisdom.com/bitcoin/difficulty, plug in your hash rate, take the resulting expected daily earnings and multiply it by 0.96.