$20/2 vs. $50/5 SnG's on Party

[PokerProdigy]

Approximately how long does it take to finish a $20/2 sng at party poker? Approximately how long does it take to finish a $50/5 sng at party poker? Approximately how much money (aka roi) can one make on the $20/2 and $50/5 sng tournaments?

The reason I am asking is because I am wondering whether playing the $50/5 sng's are really going to make me much more money than the $20/2. I like to play 4 sng's at a time. It seems that the $50/5 sng's are only going to be marginally more profitable than the $20/2, because the competition is harder and they take longer. Anyway, this is just a educated guess because I have not actually played the $50/5 sngs so let me know what you guys think.