I first got into the DJ Max series thanks to the Vita, so this is really my first "classic" DJ Max game I've played, so its great news that its basically a "best of" package from the earlier PSP games...
Its pretty straight forward in terms of modes - arcade mode which is your standard "pick 3 tracks to complete", free play mode which lets you play any unlocked music on any difficulty, mission mode which pits you against tough challenges (clear X songs while only missing 10 notes, get a certain % completion score etc.) and an online mode which I believe has you face off against other players in a score attack style mode. I've not tried that last one yet though.
In fact, I've barely scratched the surface of the game. For starters, there is a lot of stuff to unlock. I've just about hit level 30 and I'm still getting pop ups after songs that tell me I've unlocked new songs/gallery items/videos etc. There's around 140 base songs in the game comprised of DJ Max Portable 1, 2 (PSP games) with around 40 of the tracks being all new to the series.
And the difficulty options... You can select from 4B, 5B, 6B and 8B - basically choosing the number of buttons you'll be using in the game. 4 button mode is "easy" mode, you only need to focus on left and up on the D Pad, and triangle and circle face buttons. 5B introduces right on the dpad and square face button that are used to hit the same note, with 8B introducing shoulder buttons into the mix. I've only dabbled with 4B and 5B so far, can't imagine how hard things will be on anything else! In addition to these modes you have normal and hard modes for songs and some even have an even harder mode if you hate yourself that much! So yeah, good luck finishing all the songs in a timely manor!
And that's it really, I've mainly been trying to get my timing down (S ranks are pretty tough to get at the moment, I've got a handful and can feel myself getting much better, but I can't imagine I'll get many outside of easier 4B songs). DLC is coming to add further games tracks (like Technika Tune) to this game, which I absolutely can't wait for. Oh, and the trophies are incredibly hard - good luck getting combo trophy for this one, you'll need to get a free play combo of 999,999 (not a typo!)