These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Diddy Kong Racing
Broken Base: The DS port. On one hand, it adds a ton of new content, like new tracks, new modes, new characters, new music, and even new fun doodads to mess with (like the Sound Recorder). On the other hand, the new quickstart is a Scrappy Mechanic, the hovercraft is much more difficult to control, Banjo and Conker are lost to the copyright gods, and trophy races and battle modes are no longer possible in single player. Fans are very divided.
Nightmare Fuel: This cutscene that plays when you go back out into the main hub area after collecting all the pieces of the Wizpig Amulet.
Padding: One gets this feeling given that the single player mode requires you to, for each world, race on all the tracks, beat the boss, collect silver coins in each track, beat the boss again, and then face Wizpig when this has been done with all worlds. If you want the real ending, you need to enter a grand prix to win a trophy in each world, beat the bosses again, and rinse and repeat the initial and coin races in a new world before facing Wizpig one more time.
That One Boss: Bubbler the octopus. And the second race against Wizpig himself.
Wizpig is somewhat excusable, given his role as the Final Boss. The second race against Tricky... argh.
Tricky's not too tough if you know where the shortcut in the mountain is.
Bubbler's second race is considered by many people to be the toughest race in the game, next to Wizpig's races on Adventure 2.
The first race against Wizpig is damn near IMPOSSIBLE unless you know what to do. You need to use the zipper trick (Let go of the gas before getting a boost) to beat it. Unfortunately it's quite possible for players to never to get this bit of info, since it only shows up randomly after bosses.
That One Level: Many of the normal levels during the Silver Coin Challenge, but especially Greenwood Village.
This gets much worse in Future Fun Land, particularly Spaceport Alpha.
That One Sidequest: Unlocking T.T. as a playable character requires beating his best time on every track. And he's good. In the original, this means unlocking the fifth and final world... In the remake, this means both unlocking the final world and buying all the tracks in the D.K. Jungle world. Of course, once you get T.T., you have no excuse for losing to anyone ever.
In the remake, getting all the balloons in the "Balloon Touch Challenge" can be frustrating for some courses. In fact, it is oftentimes the courses that are otherwise the easiest to race on where they are the hardest, since those courses are shorter and so there are more balloons in one area, forcing you to tap like mad to get them all before they pass by for good.