I had the bumbo brand tray. It turned out to be a waste of my money. I had the bumbo and my son did well in it, so I figured I would go get the tray so that he could have some toys in his reach. He would just knock them off or throw them so I would be retrieving them constantly. The only time he successfully played with the tray on was just banging a spoon or something on it. The tray is very small so won't hold much. It isnt completely level. It is also difficult to put on while baby is in it, because you have to lift the front of the chair up to slide it under. My son was small and I still thought it was awkward.
I have gotten use out of it once he got older. My son will still fit in a bumbo at 2 1/2 and I took it to my moms house when he didn't like to play in it anymore to have as a booster chair over there. Occasionally we have had not enough chairs at the table so we put him in the bumbo and tray on the floor to eat dinner. But lots of kids won't fit in them after 6-8 months if they have chunkier thighs, so I wouldn't count on getting that use out of it. And I think we have only done that twice. So not really worth it overall.