Now that I can install things again (I had some incompatibility with the Mepis repo which would prevent some unstable packages to install), I did with Midori (midori 0.2.0-1 / unstable).
It's quick in rendering pages. For opening itself it's as slow as Iceweasel and maybe a bit slower for opening new tabs.
And last but not least it uses much more RAM (like just opening it uses 60+ MB). IDK if it would be different in a pc with less RAM than mine (1 GB).

It has a sleek design which is pleasant to use, has some features lacking (like password and cookie handling) and its development is going on.