We went as three adult guys for my 29th birthday back in 2010. Belle called us a table of Beasts! But we had a great meal and the food was good, with fun character interactions. Aurora was surprised when she asked where our princesses were and my husband took my hand and said, right here!
But basically yes go for it!
Certainly not. The characters will enjoiy conversing with you just as much as they would with a table of kids or mixed with females. The atmosphere of dining in the castle is wonderful and shouldnt be missed. The food has been up and down in quality, most times weve enjoyed the meal. We have taken some great photos of guys from our table with the princesses.