The Tomorrow People/YMMV

Had to have some fun with the Special Effect Failures here.

The Slaves of Jedikiah

 * Kenny is obviously superimposed on Tower Bridge
 * The Jaunting effect used in the first season involves FX patterns superimposed over the actors. This was too expensive, and too full of Fridge Logic, that it was dropped after the first season
 * The stungun effect, first seen in this episode, shows an ellipse over the "stunned" actor. This one actually improves over a certain other show's habit of simply turning the film to negative, in that it allows for slightly better pacing.
 * When the ship explodes, it's an obvious model exploding.
 * The camera zooms in on the map that has had an optical effect circle drawn on it, causing the circle to be anchored in place on the screen as the map moves.

The Medusa Strain

 * Obvious superimposed square "light" when Jedikiah arrives on Rabowsky's ship.
 * Obvious chromakey effect during dinner between Rabowsky and Jedikiah.
 * When Peter freezes time, the scene in the Lab is shown by having the actors standing really really still, but Stephen and Carol's wandering through London is shown as though it were a weather presentation.

The Blue and The Green

 * Not a failure per se, but as mentioned earlier, the "jaunting" is now simply accomplished by a simple dissolve, which makes sense if you want to remain inconspicuous, but it's Hand Waved away as a method John discovered. So it makes no sense when Elizabeth's first jaunt is also lacking the flashy effects.

A Much-Needed Holiday

 * Obvious backdrop is very obvious.

The rest of the YMMV tab for The Tomorrow People:

 * Canon Dis Continuity: In the Big Finish Audios, for no reason other than the writer's distaste, they make a special effort, in an audio-only medium where no one need ever know anyway, to point out that the switch from tacky belts to tacky bracelets and TIM's upgrade to "mobile trash bin" form have been undone. Also, the names of several of the 90's revival characters are listed among Tomorrow People who died while breaking out, effectively writing off the entire series as a Near Death Experience.
 * They Wasted a Perfectly Good Plot: The spaceship which the 90's Tomorrow People use as their base of operations and feel an unusual affinity towards, is never explored in-depth beyond the "Origin" episodes, and what's there is cryptic at best.
 * WTH Casting Agency: Christopher Lee as the immortal Pharaoh Rameses.