The best Batman? The right Wonder Woman? A new Spider-Man? All those questions will take a backseat soon to "Who is the best Quicksilver?"
As 2014's X-Men: Days of Future Past and 2015's Avengers: Age of Ultron are both going to utilize the only known shared characters between the studios Wanda (at least in Avengers) and Pietro Maximoff in their big tentpole films in 2014 and 2015. It will be one of the big debates among fandom "Who did it better?"
Taylor Johnson is already well known for his portrayal of the title hero KickAss in the two films of the same name (of which Peters had a supporting role in the first film) and is sure to get a boost in recognition from the upcoming Godzilla (which he stars in alongside Elizabeth Olsen his Avengers sibling). I believe however his best work so far was the 2011 Oliver Stone film Savages, if you haven't seen it pop it into your Netflix queue.
Peters I know from American Horror Story but since I tuned out during season one I really cant use that as a reference point, but a quick look at his IMDb page shows he received an award for that role and he has several tv credits dating back to 2004.
The real factor will be in the way the character is depicted in the two films. So far it seems like in DoFP Pietro will be Magneto's son in and around the 1970's this leads me to believe he will be aligned with his fathers Brotherhood and an enemy of the X-Men (First Class version). It is also interesting to note that in X2 when Mystique accessed Lady Deathstrike's computer to locate a captive Magneto, a file was seen in a pc folder labeled Maximoff (2).
Aaron Taylor Johnson alongside Elizabeth Olsen will be introducing the siblings to the MCU which I feel is slightly more Ultimates than 616 especially in its Avengers film. They do take a little from each so its safe to say they will be close, Pietro will probably be over protective of his sister and SHIELD will probably be their way in, not as adversaries and then recruits like in Avengers #16. I sincerely doubt Disney will even hint at the incestuous overtones of The Ultimates comics,
If thats the case then it will be hard to compare the roles as one is possibly a villain and one is probably a hero. The special effects will also play a part in peoples liking of the character and I'm sure each film will seek to have its speedster stand apart from the other. Whedon and company will have the advantage of seeing Fox' version with at least 10 months to go before their film debuts.
I'm thinking Peters is more of a cameo in DoFP but if popular he may have a bigger role in X-Men: Apocalypse alongside possibly Fox' version of Scarlet Witch since that movie is said to focus on the first class cast (won't they be the third class by that time?..a young Jean Grey and Cyclops?.. one can hope!)
Either way another thing to note is for action figure collectors who so far have one comic book version of both Wanda and Pietro you are about to break out that wallet and find yourself buying a few Quicksilvers very soon.
In closing let me also note that over at DC Grant Gustin is Barry Allen/The Flash (soon to be) on the TV show Arrow which will get at least a Flash spinoff pilot soon. As WB ramps up its production on the Man of Steel sequel to feature confirmed appearances by Batman and Wonder Woman rumors of a Flash cameo have also spread, though no confirmation has come forth. If this turns out to be true and since Greg Berlanti producer of Arrow has stated that unlike Marvel the DC movie and TV universes are not shared as far as he knows, then we will probably be getting another actor cast as Barry Allen in the near future. Unless DC/WB decides to use Wally West in their movie universe but I doubt that since it will cause confusion to the non comic informed viewer with The Flash(s) having two separate secret identities.
All in all it is an interesting time for speedsters in the live action superhero world, but all of this will revert back to the only real question that matters "Who is faster The Flash or Quicksilver?..Yes, in the comics we know its The Flash but the limits of their powers have yet to be decided on screen.