Well, I guess from the picture one can't tell what MHz/GHz it has, I am sure they made same looking ones with different MHz/GHz numbers (I am pretty sure there was even a 2x 1,8GHz, as far as I remeber from lowendmac.com).
I got another lucky buy on Ebay though. Not that cheap as the one with the powerlogixx + Sonnet USB2 Card, but very nice indeed, I'd say.
I got one for 71eur including shipping, with Acard 2x SATA Controller (the model with 4! switches for raid and so on) and a 2x1,8GHz Sonnet CPU. (Plus 3x256MB RAM and the rest of minor interest).
Another one I got for 20EUR with an ATI 9200 AGP (a flashed one with small form faktor, nice for Cubes), plus a Sonnet 1,2GHz, with passive cooler, a DVD-DL Drive and 3x 512MB RAM and the a bit rare HDD-"bracket".
I think I got a good price (it was declared defective, too), but there is still something I am looking for: a quieter, cooler and less power hungry CPU upgrade with the same or more power. I will try to get a hand on a sonnet 1x1,8GHz (other chip than 2x1,8GHz), since powerlogix upgrades are rare on EBay.