I like my games harder anyway. I'll play the US versions.
Vic's version of "harder" is the laziest possible way to make things harder: buff enemy stats, debuff your stats.
Exile isn't that bad though you can really feel the inflated boss health at times - inflated health when coupled with Telenet's typically shoddy programming/design makes for some less-than-ideal situations.
I'm not sure how WP was improved other than some parallax in a few stages - the game is practically un-salvageable in its original state with its awful hit detection and camera placement.
I am happy to try out Popful Mail without the wonky "improvements" (read: not improvements) Working Designs made to the mechanics of the game. Popful Mail is a lot like Silhouette Mirage in that both have fantastic and fitting localizations (minus some bad pop-culture references here and there), but have so many mechanical/design changes in them that are truly baffling and bring down the game in the process.