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.
A lot of people were unimpressed with the final boss of FLUX; it's an empty room, the object being to bounce the ball 15 times without missing. It may seem relatively uninspired — that is, unless you've lived long enough to remember the Atari2600 games, and you suddenly remember the original Breakout, and you remember what happened after you destroy 2 entire walls of bricks. The answer? Nothing. You're left with an empty room and you can simply bounce the balls around forever until you lose them all, because there is nothing left. The game is over.
Furthermore, Neuse said that in Runner, they added the ability for CommanderVideo to kick down walls because they were so annoyed at the walls in Pitfall. Similarly, in FLUX, you can bust out of the empty Breakout room and into the beyond... because, after all, CommanderVideo cannot be stopped. Not even by the very boundaries of that which he's been in as long as he can remember. Not even... by life.
In RUNNER, after Radbot assists you in "The Source", you run by a bunch of "Burger Mouth" billboards, then Meat Boy comes in to help. Think about it...
Game Breaker: The bosses of the second and third songs of VOID contained a horrible infinite score exploit if you stall forever while in "super" or "ultra" mode and steadily gain points. The updated version of the game disables the automatic score gain of those modes at the bosses.
In RUNNER the background textures are wonky and the game is susceptible to graphical slow down. It also suffers from poorly executed 3D effect - it only works in cutscenes and for the background imagery, while the levels itself remain in full 2D, which seems really strange given the fact that all other five games in SAGA have a nicely executed 3D effect.
In VOID patterns will flat out just appear out of nowhere.
The music in some cutscenes and levels can get out of sync.
Sometimes, the music in "Perception" in FLUX can just plain not start.
This one appears to have been fixed, but in RUNNER, sometimes, when starting the level "Rusty Warren", the game will freeze.
Despite this it's still playable and enjoyable, and the remaining three games seem more or less okay.
Tear Jerker: The ending of FLUX, as well as CommandergirlVideo's crying at the end of FATE. At the end of the former, you get kicked out again to the menu while Strange Comfort plays as the camera pans to the blue planet.
Level 1-11 in RUNNER is disproportionately harder than the majority of the game. No wonder there's a Steam achievment for passing it.
3-2 Retro Challenge makes many perfectionists want to run out and murder the level designer.
BEAT is generally regarded as one of the harder games in the series, but the fifth section of Descent stands out in getting people stuck. Immediately, you have to survive a difficult challenge involving hitting erratically bouncing beats with a tiny paddle. If you managed to get through that, soon after comes an onslaught of bouncing beats that jump across most of the screen and move so fast that it is very difficult to spot the pattern. You'll be lucky to survive through Nether unless you know where to move beforehand.