回复：请问除了H1可以延三年以外还有什么好处吗?

Keep your H-1, it is more flexible than EAD, e.g., in case your I-485 is denied, with H-1, you can still stay here, and prepare next application. If you use your EAD, in case you case is denied, you have to leave here, b/c your AOS is finished.
On the other hand, your company will pay you H-1, and you will pay you EAD.
However, if you have second employment, you may use EAD, otherwise you need another H-1. After all, the chance of 485 denying is slim.
just my 2 cents.