what's different between the DMC 3 special edition and this?

[Rossflex]

you get 1-3 in this seems like the better deal

[DarkJuda On Deck]

DMC 3: SE is included in this collection.

DMC 3 vanilla never released on pc actually.

As for the differences between the standalone DMC 3: SE and the one included in this collection, let's say the standalone was a native port but very poorly executed, lots of game breaking issues, horrible port altogether (on par with original RE4 by sourcenext, the same ones that did that horrible port) and this one here is semi emulated alongside DMC1 and DMC2, it works fairly well from the get go with very few non game breaking issues (some low res textures/effects here and there), but asks a lot if computing power to run well considering this is just a PS2 game, and it can't go past or below 60fps since framerate is tied to physics/animations.

[gold ;(]

dmc 3 special edition that is on steam shouldnt be even on steam. It has a terrible port and because of that you need to install mods to fix the performance, low resolution and make the controller work.

hd collection contains 1,2 and 3 on hd textures, lights, efects compared to the originals.
in this version dmc3 works perfect with no performance,resolution,etc problems.
the only bad thing about this collection is if you don't have 60fps all the time on cutscenes the audio will de-sync (cutscene only)

[Sephiroth]

the collection is just better in every way ive beaten 1 and 3 on DMD mode and i didnt have any issues and it has good controller support and has 16:9 support which the originals on ps2 didnt have