How can you compare Heya with Banyan Garden. They are total different.
For 喜雅, it don't have different Tunnel to MTR station. They don't have a right size Club House, Swimming Pool.
If me, sure I will buy 4 small Dragon instead of Heya series. They are still other Heya series coming, Heya Crystal, Heya Green, many many Heya xxx are coming.
Besides, Heya only provide small size house, but Banyan has flat with 9xx sq ft.