Hello hello! I just received a copy of Gradius Portable--imported of course. The game is excellent! Anyone with homebrew can play Gradius 1-3 on emulators, but this is SO different. The FPS is way better, and the game's speed seems boosted a little bit. I have mastered the first few stages of each game, but when I picked up Gradius Portable is was much more difficult, for some reason.
They added a lot of tuning to the game, also, such as a difficulty control (I keep at 4 - Normal) and a "Semi-Auto" power-up select, which automatically buys Speed up, then missile, then option. I usually turn off the semi-auto, because I like to customize my stuff a bit more depending on situation...
Also, the Gallery, selectable from the main menu, has all the music from each game... including an AMAZING track of Gradius 1 that is a piano version of stage 1's music.
For those of you who thought about buying this... Do so! You might as well buy the import, because the only thing I've seen so far that needs to be translated is the Save menu (You hit "Save" in English and then the "Do not remove your memory stick" warning is in japanese, and when it asks if you want to overwrite, it is also in japanese) Other than that, every menu, gallery option, title, etc... is in English.
The game DOES require 2.5 (first game I've bought that requires it...)
It was definitely worth my $50 (purchased on ebay, it's $60 on lik-sang)