Isn't MPEX the only place you can reliable underwrite and buy options against the USD value of BTC?

I would say this is value enough, given April 2013 would likely have been a lot worse had MPEx not existed.

The shareholder report for March: http://trilema.com/2013/mpoe-march-2013-statement/ kinda shows that.

Additionally, those who bought MPEx accounts in 2012, and as well bought S.MPOE before the 2nd batch of the IPO are likely all millionaires (in USD terms) at this point.

So to be honest, I really don't see how it is a scam. Perhaps the other businesses in their infancy seem a tad questionable, but MPOE-bot I think has proven itself as a valuable asset to the Bitcoin world as a whole.