Anyone know the weekend hours for Petit Casino in Orient? Will be arriving Sat evening- curious If they stay open later on Sat and if they are open Sundays - thank you <img src="http://www.traveltalkonline.com/forums/images/graemlins/Joy.gif" alt="" />

I think it is open until 8h00pm on Saturdays and yes , they are open Sundays

This post has the hours from the summer, so I would assume that their hours are similar now.

Per Bruno, current hours for Petit Casino are:
Monday to Saturday : 7.30am to 9pm
Sunday : 8am to 8pm

How are the prices vs Simply?

I personally don't honestly know. I haven't been in Simply for a long time.

Simply is cheaper than Petit Casino. Petit Casino price are in accordance to the tourism area where it is located while local resident mainly shop at Simply, Leader Price or Super U.
Super U, by the way, located in Marigot where Match was formerly located is a very nice supermarket, with great products and great price (IMHO, the best on the French side) <img src="http://www.traveltalkonline.com/forums/images/graemlins/handshake.gif" alt="" />

During both of our trips to St. Martin, we ended up buying more than we needed for food and drinks. In the end, it may have been cheaper to just buy on demand rather than try to plan ahead and buy for a week or so at one time. So the price difference works itself out unless you're really precise with your purchases.