Difference has to be understood between Korean replica and original Korean phones .
Korean replicas : NO
Korean device : All the way
Generally original Korean devices are of three major brands ,ie Samsung ,LG and Sky reason being these three are Korean companys . Mostly Korean variants have better features than international versions .
Cons
1. Antenna for TV (useful only in Korea ).
2. Korean network provider logo on the phone .
3. Phone software is full of Korean language and apps .
[U]Pros
[/U]1. Korean versions are first to receive OS updates . F 180 (Korean Optimus G ) has received Kitkat update few days ago whereas E975(International Optimus G ) will take another 2 months .
2. Sometimes better hardaware than international versions . S3 international has 1 Gig of ram whereas SHV E210 (Korean s 3 ) has 2 gig. E970 (AT&T version Optimus G) has 8 MP cam and 16 Gig storage . F180 (Korean Optimus G ) has 13 MP cam and 32 Gig storage.
3. All the Korean language, apps and bloatware can be easily removed and phone can be loaded with international English OS .
4 . Price difference of almost 8-10 k from international variants 
Hope this helps .