I gave in today.

Tiagra crankset 170mm 52-39 ($130):

CO2 catridges and adapter ($18):


Here's the worn-out chainring. Worn chainrings have sharper looking teeth than normal due to wear of the teeth sides by the chain:


Here's the brand new unworn one. A wave-like appearance (pictured with 'Missing Link' on the new chain):


Cassette (12-25) was replaced too.

Yeah, my handphone camera is badly out of focus with no macro function etc. Sad case. Something is seriously wrong with it (the lack of such design features I mean).