I just completed the Mass Effect and have to say about the subject:The winner between them is clearly is The Witcher even without EE.Here is why by components...Let's start with the RPG elements:1) Main story: The Witcher (with the knock out)Story in the Witcher is original, has nice twists of the plot, complex interaction with the NPCs, player can choose sides, which don't have clear moral aspect, choices made in the game affect the future game play.Story in the Mass Effect is banal and repetitive from many previous games; no significant twists of plot, right from the prologue we know who is the main evil guy whom we meet in the final fight, your choices don't matter except for the altruism/selfishness stat that gives you nothing at all, dialog choices do not branch, you are mildly pushed to ask about everything, the main quest is very short.2) Role playing system: The WitcherThe system of skills in the Witcher is quite diverse and you have to plan your development, you make your own 'class' as you desire. Alchemy is very well made, necessary and useful.The system of skills in the Mass Effect predetermined by the 'class' and your development doesn't matter because your enemies are always made to match your level, which makes it less important.3) World exploration: The WitcherThe world in the Witcher is very detailed and there is no place that looks the same (even caves and huts looks different). Each location has the unique feeling and style. Though the unlimited free exploration is not possible.The world in the Mass Effect is larger but the uniqueness exists only along the main quest, which also sometimes raises the suspicions of the copy paste (i.e. corridors in many occasions looks exactly the same). The locations are very ascetic on details, a lot of the same boxes placed around only for the sake of hiding behind them because the game expect you to fight in that particular place creates a feeling of unnaturality. The planets all look alike and traveling on them in the Mako is very repetitive. All buildings on those planets are the blatant copy paste with bunch of boxes put inside in the different configurations. All starships that you board looks like there is only one type of the starship in the whole human fleet and it doesn't matter if it's a freighter or a frigate. 4) Side quests: The WitcherThe side quests in the Witcher are more various and well made than in the Mass Effect, in which you almost always have to kill somebody in the standard bunker on the far away planet. There are nice side quests in the Mass Effect but very few.5) Inventory: Even (both poor)The original Witcher had very poor user interface for inventory and a poor method of picking up objects. The Witcher also had a very annoying desire to sheath the sword all the time when you don't need it. The Mass Effect has tons of equipment that can fall from your enemies but it's all generic and basically text based. While you can have a new gun you don't have a feeling that you have it, just stats of your gun changed, nothing more. The game forces you to pick all the staff that lay around or convert it in to the omni-gel, which you have to do one by one in a very repetitive and boring process that requires a lot of mouse clicking. The game's buy/sell interface is very poor: you don't see the parameters of what you sell right away, you are unable effectively compare the stats of the items that are not mounted on your character. Items in the inventory are not sorted well like in the Witcher but at least the Witcher has a visual representation of them while the Mass Effect doesn't have.So, as an RPG The Witcher is a clear winner.Lets go to the technical execution...6) Bugs and problems: Mass EffectThe Witcher (original) crashed more often than Mass Effect for me. Yes, Mass Effect also crushed and had one place where it crashed all the time if you choose certain actions. But overall Mass Effect was very polished and ran smoothly.7) PC/NPC Models: Mass Effect The Witcher has many quality models but repetitiveness and overuse of some of them were too flashy. Mass effect has all the NPC characters different with very good facial animation. Gestures during conversation looked convincing. Ability to create your own look is always a nice touch though taking a character from the books in the Witcher left that option out. 8) Graphics: The WitcherThe Witcher has very impressive set of graphic features that makes people drop their jaws if they see it on the full details. Special effects are done very well.Mass Effect in general is very good but on full details dynamic shadows look not good. Textures on the walls and the ground are very primitive (monotone colored walls, gray floor etc.). Terrain on the planets is very poor, just the relief and nothing else. Some special effects are very impressive, while other don't.9) In game action animation: Even (both excellent)Motion captured sword play is really impressive in the Witcher, finishing moves and limbs flying around adds the bonuses to the game. Mass effect has excellent animation of finding the cover and shooting from around the corners. 10) Combat: Even (both good)Combat is OK in both games but both have flaws. In the Witcher all your enemies rush at you like kamikazes, in Mass Effect indestructible RPG-proof boxes are positioned everywhere for you to use, which in places looks totally out of place and stupid, and enemies cannot hide properly behind the corner and being shot dead in the finger/antenna that stick out of the corner.11) Sound: Tastes differ but I personally like the Witcher score more, the music is more complex there and sets the mood perfectly. I'm gladly listen the sound track to the Witcher after I already finished the game but I turned the music off in the Mass Effect.12) Cut scenes and animated movies: The WitcherThe intro and outro in the Witcher are just a masterpiece of multiplication. The cut scenes are very well done. The only bad detail is a repetitiveness of the animation during the boat travels.Mass effect has also excellent cut scenes but their level of complexity and the plain amount of time and work put into it is noticeably lower than in the Witcher.As you can see the Witcher wins an the majority of the categories. The only problems of the Witcher were related to the bugs and related problems, which just shows that the Bioware is just much more established company to allow itself not to rush the game towards release.