Upgrade SE K610I (CID53) to SE W660 or higher?

I am considering UPGRADING the SE K610I to higher model. I need some advice and answers.

Q1: Is W660 the only model or is there other higher models suitable ?

Q2: Will upgrading improves the K610i to Walkman sound quality ?

Q3: Will upgrading enable radio reception for the K610i ?

Q4: My K610i is CID53, suppose I use W660_R8BE001_MAIN_GENERIC_FY_RED53 and W660_R8BE001_FS_EUROPE_4_RED53, is upgrading simply OFLASHing these files into K610i with JDflasher ?

Q5: Is this Custpack file W660i_CDA102804_86_R2A_Singtel_Singapore compatible with the above 2 files ?

Side Issues:

I want to enable K610i or W660 to read MS Word files.

Q6: Can I use DOC VIEWER_1.0.9_SE or MOBY EXPLORER_3 to enable K610i or W660 to view MS Word, Excel files ? Any other recommendations ?

Q7: These are .JAR files, how do I install such files into phone ?

Many thanks in advance.

You must use same custpack with FS..
Example

FS EUROPE_4
and custpack EUROPE_4

Problem solved. Thanks everyone. CLOSED THREAD.