The main problem with any watchface app right now is that its an app that runs on your watch not a replacement stock watchface. Before you buy an app just remember that anyone and their dog can make an app and put it on the play store. There are some great developers out there that have my support, however I'm not going to pay hard earned money to be a beta tester just because some guy claims he's a developer. There's a reason why big companies spend so much on research and development before they post an app.
Device: Samsung Galaxy S Telus Fascinate 3G+ (SGH-T959D)
Firmware: Android 4.1.2
Rom: AOKP JB M1
Device: Sony Smartwatch 2 (SW2)