Got my 1520 last week Friday, thought I'd share my thoughts/perspective to those considering getting it still, even with the 930 around the corner (hopefully).
I've used Android phones since 2010 exclusively (HTC Desire > HTC One X > Samsung Galaxy Note 3) and ended up also getting this 1520. I've always been intrigued by Windows phone because it looks awesome, but was always put off by the lack of apps in the app store, and supposedly poor Google integration (I use chrome, gmail, hangouts, etc).
Anyway, coming straight from the Note 3, the size wasn't too jarring, but it is still bigger than the already big Note 3! However, that screen more than makes up for it - it looks amazing. As for the rest of the physical parts of the phone, it is top notch. I used Nokias before the days of Android and expected good build quality, and was not disappointed. Also, having a camera button is great! Too few android phones have dedicated camera buttons.
On to the OS, as soon as I got it I also got the Developer Preview of 8.1, so no experience with Windows phone except for 8.1. Something I immediately noticed is that it is blazingly fast. The Note 3 on Android 4.4 was fast, don't get me wrong, but it feels like on another level here. Very smooth and fluid animations, things happen as soon as you press anything on the screen, overall great experience there. I was also surprised how many things are available in Windows Phone settings that aren't available in stock Android, and you would normally find it in a OEM skin like TouchWiz or HTC Sense. For example, customisable quick settings in the Action Centre drop down, which actually I only found in custom ROMs for android, not even OEM skins.
Finally, the app store. The one disappointment I still have with Windows Phone, but far less painful than I thought it would be. The only thing I am truly missing is Chrome (never gonna happen?) and Hangouts (possible, perhaps... Google did release developer APIs for Windows Phone a few months ago, who knows!). For YouTube, the browser is fine, and there are apps like MetroTube and MyTube that have received high praise but I have yet to try them. For everything I else I use (RSS News reader, reddit client, Whatsapp, Gmail, facebook, twitter, maps (nokia's maps seem good so far), dropbox, deezer, manga reader, and quite a few more, there are official or good alternatives on the store. (In fact for dropbox, I am using cloudsix for dropbox, and I dare say it's better than the official dropbox apps on iOS and Android).
I am having some teething pains though. I don't understand how sharing works! Sometimes I can share to Whatsapp, sometimes not. Seems inconsistent at times.
I also am having a weird issue, but this is probably due to it being a developer preview, but my Auto Brightness causes a colour shift on the phone. If I set brightness to low, medium or high manually, it is fine, but as soon as I enable Auto Brightness, it shifts all the colours and completely changes some to make the interface and pictures look very weird. I've settled to just setting the brightness manually but would prefer using auto brightness - I haven't had much luck finding out what's the cause or how to fix, so if anyone knows it'd be greatly appreciated.
I'll continue my Windows Phone trial and who knows, maybe I'll stick with Windows Phone for a while
