I believe that there is no real comparison.
Both has their pro's and con's
It all depents on what you do with it and how you use it.
And you cant count 8.1 in this race, becaus its stil under development and 4.4.2 isn't
Droid comes with many preinstalled apps, for those who use them its great but for others its called bloat.
The biggest handycapp of Droid is the OS itself, it almost needs a supercharged pocketcomputer only to run the OS smoothly.
The OS is only needed for the main operations of your Phone, to start a phonecall or to launch a app.
If your Phone already has a big load of running only the OS than it alsmost must have a deathstrugle of running a heavy app
A lot of apps in the GPlaystore dont even work correctly, not only because they are outdated or abandoned,
but there are to mutch differand kind of hardware.
Just look at the devices of one or two years ago, they hardly getting anny support.
I got a P5100 Tablet, also know as a tab 2, quite expensive but already called obsolete, no updates no support
The only way to keep them alive is trough custom roms, made by diehard fans and developers, not by Google/Android
Android is a nice OS, but in their race of succes they forget the ones who spend their money on the last years models.
I got two Samsung Gio's and a Htc desire, al in good shape, but almost useless, okay they are low end, but what with the S1 and the S2..the higher segment, they are also dead and buried by Google/Android.
Droid is good, but only for the highend models and for howlong? a year? ( if you are Lucky ).
Now i look at my cheapass L 520 Started with WP8 ( Gdr1 ) soon after that Gdr 2 Amber, and now running official Gdr3 Black and is in the race of WP8.1 and that for a 100$ Phone, Bravo MS they dont forget their last years models.
( just for the record it has run on WP8.1 DP, but downgrade it back to 8, had no issues on 8.1 ).
I like the freedom of Droid, only for sideloading apk files.
But hate their lack of support.
But tell me, if Droid is truly the holy grail and the answer to all things, why are people always driven to root there device or using a custom rom.
Is that because Droid is so great or does it really miss something.
I know the answer, because i have bein there.
There are a lot of apps who just don't work on a unrooted phone or tablet, call it a flaw in the system but it stil proofs that even Droid is not perfect.
Wp has its shortcommings, but the things that does work, works great, wish i could say the same about Android.