Quoted from pinballcorpse:

Tons of discussion both pro and con on many forums.
Let's assume we are talking about a fully working game. If the Megatron trough is not working right or the miniplayfield is not working or the anti-loft drop target plastic is not installed, those things start you off on the wrong foot. And those issues were part of what started the TFLE disdain in the community. But that is not the focus of my post, since in my mind, those issues can be addressed and should have been by any owner by now. Regardless, even after they have been addressed the love is not there for many.
I love the game, but I think I am in the minority. I can appreciate why people would not like this game, and I had posted from day one I knew this game would frustrate folks.
Despite the various non-gameplay complaints about TFLE easily found in the archives, I think the most basic way to explain why the game is not well-received among the playing/collector masses is as follows:
TFLE is very challenging to beat, but lacks the front-end candy and ruleset help-alongs many players/owners want.
Specifically:
TFLE is *strictly* dependent on goal completion and does not allow for simply playing a mode to qualify for the miniwizard mode (Sentinel Prime/All Hail Megatron/Roll Out; you pick the name). So if you cannot get to that stage, Cybertron is going to be even worse and far out of reach.
Many popular games with mini-wizard modes have some portion of the game that allows for a player to have simply "played the modes or multiballs, but winning was not required" Alien Invasion in TSPP, TABA in LOTR, Battle Royale in S-M, Bat Signal multiball in BDK come to mind to name a few.
In TFLE, finishing the timed modes is imperative for the larger goals and finishing any single mode in one try is challenging. Doable, but most players will need multiple tries even with the Allspark award time extended.
The second are where many games grab players is with multiballs that are not that difficult to start.
Both TFLE multiballs (Megatron and Optimus Prime) are hard to start requiring several shots. Megatron is particularly difficult for players since the scoop is tight. Balls do not randomly end up in the lock. (BTW-I think couch mb in TSPP is one of the hardest mbs for casual and skilled players to start).
When TFLE mbs are started, they are very difficult to win (again imperative for deeper goals) regardless of which faction you start with. The lack of multiball progression toward a SJP turns many players off. In TFLE, winning the multiballs is a must so not being to save your progress mb to mb is a major sticking point for players.
The other front end candy in games is the toys. In TFLE, operation of the Iron Hide mini-playfield is not intuitive for players and getting the rhythm takes many games. Also each successive round takes 8 shots to start, so it is laborious. Also it begs the question-what am I doing? In factory settings there really is no scoring objective that is meaningful. I suggest setting Special = Extra Ball to have a goal worth playing.
Another TFLE gameplay complaint is the lack of flow of the ramps. I think flow complaints are a pile-on after thought given all of the other frustrations people have. It is true that having the ball go into the Iron Hide playfield every time does not make sense, but it does not kill the game whatsoever. There are popular Stern games that are more liked where a flipper shot to return inlane shot takes longer than TFLE. LOTR immediately comes to mind with its POTD. The Tortuga disc in POTC is another example. In TFLE multiballs, balls sent to the ramps actually give the player a moment to breathe, since all the orbits return the balls to the flippers. The game is plenty fast and flows fine.
The irony of statements that TFLE ramps "kills the flow" is that games that give players no time to breathe-almost pure flow, like Iron Man are complained about as being too fast and drainy.
Those are my basic takes on why the game is not popular.
I feel TFLE is soild, but perception is everything. There were several things that alienated people about its release and not getting over that, focus was turned to gameplay where players were smacked down with no candy.
The game warrants some minor tweaking by the end user to make the game more fun-for example as I suggested-let special= extra ball. The outlanes need rubber grommets to allow for nudging. There is too much to do in the game to have so many side drains off the metal and plastic posts. Keep the outlanes opened though.
I think if Stern had added mb progression into the rules that would have drastically changed how people reacted to the game.
Anyway, play it as much as you can first, don't just read reviews to decide. Unlike TRON LE which is so hard to find, there is no hurry to buy TFLE since they are around. If the game clicks with you then go for it.

Quoted from ovfdfireman:

I love the theme and love the game, it's a keeper, but if you played it and don't like it, why buy it? I played it at expo and fell in love.....