On my IP-036 I have the Xmipllay IP-SP6 zero offset 31.6 x 400mm post in 3k gloss. Works fine, no complaints. On my IP-057 I have the Easton EC90 post. The Easton is UD Matte, about 2x more expensive, and looks very nice. However, for spending 2x the money, the seat post doesn't do anything more than the one from XMIplay.
If you want to save money, go with an XMIplay post, if you want something that is even higher quality but cost more, go with the Easton or similar.
I've always liked Thomson seat posts as well but they are only available in AL, are pricey, and not as light. However, they are made in the US (Georgia) so if you feel guilty about having a Chiner frame, you can balance out some of that guilt with an American made post
.