I considered using a Component in the beginning and found out that most of my use cases were Panels anyway. I admit that it can lead to one superflous nested div in the domtree, but given that there is usually only one instance present at a time, I found this acceptable.
On the other hand, layouts are rather easy to do and titles, collapsibles etc are just one line of code away.
Is there a strong argument I'm missing?
I use it like
Btw: When dragging such a window, the ghosted dummy shows inner window borders, what is somewhat confusing, since my window doesnt have those.
title : 'Text & QR',
width : 400,
autoShow : true,
html: Ext.String.repeat(' asd gds kha wsdawc lsn', 10)+'.',
xtype : 'qrpanel',
textToEncode : 'hello qr world'