The main positive thing about XDA Labs is that it offers a payment tool that's very fair to the app developers. In Google Play for example, developers receive about 70% of the sale of their app, while in XDA Labs they keep 100%. If that's weren't good enough, you can also pay through PayPal or use Bitcoins.
Another great thing about XDA Labs is that it supports Xposed modules. Right next to the app tab you can find the module tab where you can conveniently install any one in a matter of seconds. Of course to do so, your device needs to be rooted and have Xposed installed.
XDA Labs is an excellent app store. While it may not have as much content as Google Play, it does offer much more quality. Also, its support for Xposed modules is extremely useful for anyone who uses this framework.