I just tried QRZ Logbook for a half year now, but I am not sure if I will continue. I logged 525 QSO's in it. Before that I logged all my QSO's on a spread sheet in Excel. With filters in Excel I can search on all different kind of items. It can tell me quick how many radio amateurs I worked with 5 watt on 20 meter for instance. With QRZ Logbook I can't search for how many DXCC or anything else. And I am dependent of a internet connection. When it fails I can't log or look in it. So I think I will return to my spread sheet in Excel. Also, it is easy to make a quick back up on a USB stick.
I made a QRP qso this morning with CW on 14060 KHz with RZ3ZQ Victor from Belgorod, Russia. And this afternoon OM3LL Ivan from Slovak Republic.