I'm liking both pairings.
For me, Chai Rong and Sa are the cutest when they're not bickering. I don't really mind their bickering scenes, but I'm just ready for Chai Rong to fall more for Sa and vice versa already ^^ Whenever Pope give Sa those smiles/smirks it's just so cute ^^
I love Chai Lek and Si from the start. I really wish they got more screen time together and like Chai Rong and Sa, I can't wait for both to fall for each other and realize it. For me, Si's character is the one I can understand the most and is my favorite out of the four ^^