Staying at Oasis Viva Beach in Cancun?

Travel Info
Quick question about the Oasis chain of hotels.

I stayed in the Cancun Palace last time I went to Mexico and I was able to try the food from the different Palace resorts; i.e. Beach Palace, Sun Palace, Moon Palace.

I was wondering if I am able to do the same when I am staying at Oasis Viva Beach. Will I be able to just go into the Grand Oasis and show them my wrist band in order to eat there for the All Inclusive plan?

Also how is the Isle de Mujeres? Is there a cheaper way there then taking the excursion I see on sites like expedia, orbitz, or hotwire?

Travel Tips

You will be able to go into all the Oasis resorts except for the grand Oasis and sample the food!

P.S. - When I went to Cancun I stayed at the Barcelo Maya Beach (in the riviera maya). It is a very nice resort! I would reccomend it to anybody!