I voted 'both' but for the most part I give loose timmy hay as well as orchard, oat and botanical grasses. I did give loose brome but it was shortly after that that one of my boys developed bloat so I was too nervous to give it to any of them after that. It may not have been the problem but I wasn't risking it b/c bloat is not fun to deal with.
I do have the cubes as well but honestly none of the chins really chew them much and they tend to just kick them to the bottom of the cage or pee on them. Doesn't stop me from putting them in though, just in case. Seems I like to waste the little bit of money I have.