Shares of Melco Crown (Nasdaq: MPEL) have been on fire in 2011. Like a hot roller at the craps table, the company can seem to do no wrong. But like any game of chance, the run can't last forever. So when will it be time to take your chips and run?

Get out while you're ahead
I hate leaving money on the table when a stock is hot and price doesn't seem to matter, but I can't make the argument that Melco is a good value right now. As I pointed out last week, Las Vegas Sands (NYSE: LVS) has a lower trailing enterprise value/property EBITDA ratio and has a casino opening in the next year. Melco Crown is more expensive by this standard than Sands, MGM Resorts (NYSE: MGM) and Wynn Resorts (Nasdaq: WYNN), which all compete in Macau. Valuation is the biggest thing that concerns me right now.

Now that I've given the sell argument, let's turn this around and see why we should stay in the game.

You're hot; don't walk away now
Melco Crown is a relatively small company compared with Las Vegas Sands and Wynn Resorts, meaning it has more potential to grow. It also just bought a 60% stake in Macau's Studio City, which will provide growth in the not-too-distant future. Altira and City of Dreams have been finished for a while, and without any new developments on the horizon, it was hard to see growth exploding until this purchase.

If you really think Melco Crown has room to run, I think you have to argue that Melco could easily double EBITDA margins and still not catch up to Las Vegas Sands' casinos. An EBITDA margin of 15% last quarter left me not only disappointed but asking "where's the money going?" Melco may be paying more than competitors to junket operators, but the company's margins are still disturbingly low. If Melco can rectify this problem the stock could continue its hot streak.

Place your bets
I've laid out the sell argument and the upside argument. What do you Fools think?