So I'm looking to buy a new cheap mouse (20eur max), and the WMO seems to be the perfect fit. However, I'm seeing at least 4 different models with a price range from 10eur to as much as 40eur.

I guess the 61 is the oldest one (1.0?) and is a piece of crap.

I'm seeing many people recommend the 69 (1.1).

But what about the 7x models? Are they just a better, updated 1.1? Do they have a new sensor? I've found both a 74 and a 76 for 18eur, is this a good price? On the other hand, there's a new 73 for 40eur.

Which is the best one?