* BreatherLevel: While the "Good Thang"/"[[Music/BillySquier The Big Beat]]" mix can be a bit tricky, neither of the J. Period Presents mixes are anywhere near as tricky as some of the mixes you'll do to unlock them.
* ContestedSequel: It's heavily debated which game has the better soundtrack. The first game primarily focuses on rock and hip-hop from a decent stretch of decades, with a decent mixture of famous, {{One Hit Wonder}}s, and fairly underground artists. Meanwhile, the second game focuses mainly on modern radio hits with less rock music.
* EvenBetterSequel: While the soundtrack of which game is better is heavily debated (see ContestedSequel above), there's no doubt that the second game's improved gameplay mechanics (with more freestyle sections, more note types, and changes to the Rewind system) make the second game better from a purely gameplay standpoint.
* ItsShortSoItSucks: The guitar career, if you can call it that, has a grand total of 10 songs you can play, 9 of which are mixes.
* NarmCharm: DJ Z-Trip's "Juke Box Hero" vs. "DJ Hero" mix is a fine mix, but the lyrics splice away mentions of guitars and rock music for turntables and instrumental hip-hop. It ends up sounding ''hilarious''.
* ScrappyMechanic: Unfortunately, several!
** Both games require you to spin the platter backwards to activate Rewind. As you could expect, this is very finicky, and not doing it at the perfect time will almost certainly make you drop your combo.
** The crossfade spikes are very finicky in most songs because of the short-burst movement it requires from the player. The success rate of said spikes can also vary from song to song; some feel like the on-beat portion is when the spike is at its peak, while others feel like it's shortly after the crossfade switch returns to the center. Needless to say it is one of the biggest offenders for dropped combos.
** Both games also require you to turn the effects dial during certain sections to get bonus points, similar to the whammy bar in ''Guitar Hero''. The only problem is that the dial is very weirdly shaped, and the thing ''will'' dig into your skin and hurt after doing it for long enough.
** For the second game only, held directional scratches are confusing and difficult to perform. Thankfully, they're used fairly sparingly, but until you get them down you'll lose a lot of combos to them.
* SequelDifficultySpike: ''DJ Hero 2'' added in not just freestyle scratches and crossfades, but also held taps and scratches.
* ThatOneBoss: In Empire Mode from ''DJ Hero 2'', Music/DavidGuetta's DJ Battle Mix ([=MSTRKRFT=]'s ''Bounce'' Remix). It only has 6 checkpoints and both players have very little advantage, and no matter how you try, David's trigger happy wits will triumph over you in the end (granted since his lightning fast wits will lock you out thus giving you a slim chance of winning). The only hope you have is to beat him to the punch and be flawless, or lose (FYI: draws don't count).
** [[ThatOneBoss That One Song]]: Let's put it this way: If any of the mixes you play are made by the Scratch Perverts, chances are you're not gonna clear said mixes with 5 stars in one go, barring the Easy and Medium difficulties. Case in point, ''Beats and Pieces'', "[[Music/{{Noisia}} Groundhog]]" beat juggle, and, god forbid, the [[Music/TheChemicalBrothers "Galvanize" remix]]. [[spoiler: For the latter you'll get a trophy/achievement if you did not manage to 5-Star it on Expert and one if you ''do'' manage to pull it off.]]
* TooGoodToLast: A breath of life into the stagnant music game genre, cancelled after two games due to poor sales.
* UnintentionalPeriodPiece: Not the first game, but the second's heavy reliance on late 2000s contemporary hits (such as Music/LadyGaga, Music/LilJon, and Music/SouljaBoy) firmly push it into this territory.
* VindicatedByHistory: The series in general, as well as the soundtrack, became better known after the series' cancellation and it's often praised as one of the most overlooked games of the [[MediaNotes/TheSeventhGenerationOfConsoleVideoGames seventh gen]].