When comparing ARC Welder vs Droid4X, the Slant community recommends ARC Welder for most people. In the question“What are the best ways to run/emulate Android on a PC?” ARC Welder is ranked 5th while Droid4X is ranked 9th. The most important reason people chose ARC Welder is:
Even though it's a developer preview, it's likely to evolve quickly as Google is developing it. Since Google is also behind Android, it makes sense to use a more official way of running APK. If they don't work, you may check with the developer so it may eventually work.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Developed by Google
Even though it's a developer preview, it's likely to evolve quickly as Google is developing it. Since Google is also behind Android, it makes sense to use a more official way of running APK. If they don't work, you may check with the developer so it may eventually work.
Pro Cross-platform
Works on Chrome 41+ on Windows, Mac, Chrome OS and Linux.
Pro Allows running apps in a Chrome web browser
It installs as a Chrome App and runs on most operating systems (Windows, Mac, Linux, Chrome OS), even thought x86 support will be put in maintenance mode soon.
Pro Can run dual operating systems smoothly
Flip easily between Windows an Android OS with ease and no performance degradation.
Pro Install apps 3 ways
Drag and drop to install or use the apps store or run .apk apps directly to install.
Pro GPS simulation
Pro Remote controller options
Use your smart phone to remotely control your Droid4X games (or customize your keyboard)!
Pro Touch screen support
Very responsive touchscreen for great game play.
Pro Free
Pro Great integration with Windows + tablets
Allows for hard or virtual (screen) keyboards, customize RAM and CPU's used, window size or full screen, swipe between Windows 10 and Droid4X, and allows for 1 folder share (local or LAN) as SD
Pro Amazing graphics
Graphics are exceptional (high end games as well as low end).
Cons
Con Discontinued
Discontinued after December 2020.
Con Not all Google Play services are yet supported
ARC Welder supports OAuth2, Google Cloud Messaging , Google+ sign-in, Maps, Location, and Ads APIs from Google Play services.

Con Only supports "arm" apk files
"x86" apk files don't work as of 20150422.
Con Keyboard input is spotty
Con No accelerometer emulation
Con Orientation mode has to be selected before running the app
Con A single app can be loaded at a time
Con Win 10 sleep mode issues
Coming out of Windows 10 sleep mode tends to lockup this emulator. Restarting the emulator seems to be the only option (emulator appears to still be running, but the Android OS is frozen - apps/icons, menu's, google store, etc. )
Con Windows Only
Con Custom "Recommand" tab screen from homepage is useless
Gives error "The Contents is not provided in you region".
Con Gyro sensing not working
Con Pressing the Home/Back/Task-List icons may cause some lag for the emulator
Con The default home screen is not customizable
Con Buttons on the auto-hide navigation bar are too small
Con No widget support
Con Native screen auto-rotation is only for 180, no 90/-90 except for some inplay games.
Con Latest version used is Android 4.2.2
