I bought the original many years ago, tried to get into it twice but never got anywhere, so I left it on the shelf gathering dust until a few months ago. I bunged it on the off chance, and suddenly it all clicked and I became hooked. I played all three games, exploring most of the side missions and classes, and made it all the way through to the end with a female mostly paragon Shepherd without knowing what would happen, which I'm quite proud of. As for the controversy surrounding the ending [spoiler]I was expecting the worst, thinking it might end mid attack a la Halo 2. Instead I was more bemused, but the more I thought about it, the more annoyed I got. After spending at least 120 hours on that character alone, the fact she died didn't bother me too much, but the massive plot holes and lack of closure did. It didn't tell you a single thing about almost all of your squadmates, and the Normandy landing on another planet made no sense whatsoever. The only way that could have happened is if they fled the battle before the mass relay was blown up (which they specifically stated before would destroy entire systems). With technology destroyed presumably that massive allied fleet I'd assembled was either wiped out as well, or stranded with no way to get home.
Speaking of that, what was the point of asset building? I spent hours doing it in the hope of seeing Elcors going into battle, massive Korgan armies making bloodrage charges and fighting side by side with Blue Suns mercs. Instead, the final scenes are 90% human. The big twist is synthetics and organics cannot live in harmony so must be destroyed in cycles - except the entire point of the trilogy is getting different races to unite. In fact, everything from entering the Citadel again seems to have been written by a completely different set of people.
So I downloaded the extended cut and chose the "blue" ending again, which it must be said is a vast improvement and ties up the Normandy and mass relay plot holes (well, aside from the fact James magically teleported from London to the Normandy), as well as giving some closure and hope for the future. Although surely the Stargazer scene is redundant now the Normandy didn't settle on that planet? That said, since he's voice by Buzz Aldrin it makes that character awesome by default. Also not quite sure how that is 1.8gb of ending, but never mind.
That aside, what a brilliant game, and indeed trilogy. Yes it did get dumbed down slightly after the first game, and I must have been about the only person who actually liked the Mako sections, since it gave you a sense of exploring an unknown world. The main strength is the excellent writing, which gave you plenty of characters you care about and an enemy that you hate. As it builds up to the final confrontation it really does give you a feeling of what is at stake, and you're the person who can make the difference. After putting so much effort into the games for the last few months, I'll even admit to getting a bit emotional at the ending as saying goodbye to Shepherd I'd spent nearly 150 hours with (on that character alone)
In many ways it encapsulates everything good and bad about the current generation of gaming. On the plus side you have epic scope, beautiful graphics and sound, strong writing and mature themes. On the other, day one DLC, making the second and third games more mainsteam, including a pointless marketing cameo in Diana Allers, and an initially rushed ending that did nothing but anger a loyal fanbase.