I prefer flattop (no playtop) to dometop or otherwise... I have smallish birds and I prefer flattops cause it's easier to hang toys at all the same level, so they come down to the perches. I do have a macaw cage dometop for my mitred, and two other "dometop" (more like curvy and house-shaped top) flight cages though... still, I prefer flattop, cause if I want to put something on top of the cage, be it a playstand, a wheel, or just a piece of board to keep the inside of the cage cleaner from outside (i.e. cage-free) birds...
I don't care for playtops too much (never owned one, mind you) as if I wanted my bird to have a playgym of sorts, I'd want it to be easy to move around (if it were for a medium sized bird), instead of stuck in one place.
However, with caiques, you could probably go either way on dometop vs playtop... the more room inside the cage, the better! But also, they'd love to play on something outside of the cage!
Considering the size of the cages, I don't think it'd matter much if you went playtop vs dometop.... as it's a good amount of space inside... if the cage were smaller I'd say dometop...
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