What is the different? and which one is best?

That's not the difference mate...the k700c is built for the chinese market, and as such has chinese characters while the k700i is for the international market and as such uses english as the primary language...it has no support for the chinese characters...and i think that's the only difference...i've seen some places mention that the k700 has only 32 mb but as far as i know both fones (c and i) are identical except for the chinese characters are present on one and absent on the other. so there's no question of which fone is better...it's more a question of what u need!

O by the way, as far as i know, the k700c has 41 mb of memory too. (tell me if i'm wrong here)

Hmm I have k700i and its have 41 mb ??

That's ok mate, we all make the occassional goof-up

Voila...here's where i kick in LOL
the K700c is designed for the chinese market in mainland china, where "Simplified Chinese" is the language of choice. however here in Hong Kong where "Traditional Chinese" is used, K700i with Traditional Chinese is offered. so there's no difference between the handsets, other than the fact they're offered in two different markets, and both have different forms of Chinese.

same goes to S700i and S700c
S700i gets english/english & traditional chinese
S700c gets english and simplified chinese

any more questions?

well,the k700c "c"that means"china"and "i" means "international"