Several things, actually.

*** WARNING!!! SPOILERS AHEAD!!! ***
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1. Heat sink clips
So they decided that they would actually rather have an ammo system than a cool-down system, and needed to come up with a plausible explanation for the change. Well, they failed. In a real world, heat sink clips would be an excellent addition to the cooldown system, but a really shitty replacement for it. It's completely implausible that it would be embraced by anyone, much less everyone. And the fact that every single weapon existing in the world at the time of ME1 has been replaced by the time of ME2 is just as implausible.

2. Questionable moral choices
Getting paragon points for endorsing three different stores as all being "your favorite store" is just stupid.

3. Romance "options"
In ME1, pursuing a romance was very much an "option", meaning you could try it if you wanted, but you didn't really notice it in the game otherwise. In ME2, most shipboard conversations seemed to revolve around luring one of your team mates into bed.

4. Liara
In ME1, I pursued the romance option with Liara. I thought it was very tastefully done (as opposed to the romance options with everyone else in ME2), and looked forward to exploring it further in ME2. As it turned out, in order to get Liara to even talk to me about it, I would have to buy the Lair of the Shadowbroker DLC. Fuck you, Bioware.

5. Planet scanning
This is very much what I meant by "all-out replaced by something much worse". No, the Mako segments in ME1 were not perfect, and could definitely be improved, primarily by making the planet heightmaps less steep. Instead, they removed it altogether and replaced it with what I can only describe as a spherical window cleaning simulator. Whoever was responsible for the introduction of the planet scanning mechanic in ME2 should not work in game design ever again.
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*** END OF SPOILERS ***

This forum definitely needs spoiler tags.

I have only played them on console so I can't compare the two systems.

I had no problems playing the games with a controller, as with any other game you need to learn the controls.
Especially with the first Mass Effect game, since it has more tactical gameplay elements.
Mass Effect 2 plays more like a third-person shooter, for good or bad.

Logically the PC versions will look the best, since consoles are not upgradeable/customizable.

I remember that the first Mass Effect game froze on a couple of occasions (screen freezes).
Also, there were a couple of bugs and glitches.

However if you read on the Steam forum for the game this seems to happen on the PC as well.
In general its always a good idea too look through the forums first before you buy a game on Steam.

Mass Effect 2 played perfectly on the Xbox 360, I did not experience any technical issues.

I made a choice a long time ago to reserve triple-A games for my consoles, and not Steam/Uplay/Origin.
Partly because of "Big Brother" DRM and partly because I've had more technical problems with triple-a Steam games than I've ever had with console games. So its a personal preference. Graphics don't mean that much to me.
It all depends on what you prioritize in your experience.

Well I can't argue with that, I hated those changes. The lack of real story fucked me off aswell.

First of all I can list the number of games "better on console" on one hand. Even the crappiest PC port is usually better than the console version, and you can use a controller if you want.

Secondly the Mass Effect ports are very good. They don't play like PC exclusives mind you, but for multiplatform games on PC they're very well done. Make sure to force AA or FXAA through your control panel for the first two games.

Nice. I really enjoyed the first game. I'm in the middle of the 2nd. I see where the hate comes from, but I don't mind those things as much, I guess. I'm enjoying it.

I never pursue romance in Bioware games.

I hope you have fun.

I like the music and the general sci-fi blue aesthetic.

I have all 3 on PC, as you can usually find them on sale on either origin or steam (ME 3 is origin only but still goes on sale, got the more expensive deluxe or something edition for like 4 dolars), and I gotta say I loved those games. On PC they all run great. But the thing is...
DLC. The charge so much for every piece of DLC, and there are several that seem pretty awesome, but they never go on sale because bioware points never go on sale, and you can only get them with bioware points. Why, it still boggles my mind to this day. So you can get all 3 base games on sale for like 15 bucks in total, but to get the dlcs for ME 2 only you have to spend close to 20 bucks. Not kiding. And the same for ME 3. So no, the DLC are way to expensive, yes some seem pretty cool but charging 25 u$ in DLC for a game that came several years ago, that's just a big no. After so much time, you just start saying f*ck it, I'll play the heck out of the games but won't spend a cent on the addons. I mean they even sell Dragon Age Ultimate Edition with all of it's DLC in it (and I got it on Origin on sale for 5 bucks, the whole DA:O experience).
For someone like me, who if I want to get games I have to get them through sales because I just can't spend many dolars (exchange rate is crippling for my wallet), it's just not worth it.

Late to the party, but I tihnk you made a good choice. I can't actually compare the PC to the console version, as I've only played them on PC, but I can say that the PC versions played very well and I had absolutely none of the commonly heard 'this is a sucky console port' complaints with them.

PC Master Race.

Console Peasant.

The real question is are they solid PC ports? And I'd say yes, more so with ME1. So no doubt, they are better on PC.

I gave you a +one for this review as it was insightful. I think I would play it on PC myself as I usually use KB/Mouse.

Really? I didn't know that :S

Found the Mass Effect Trilogy even cheaper at Gamestop for $9.89.

http://www.gamestop.com/pc/games/mass-effect-trilogy/105548