TNT-Audio has posted a review of the AudioDigit TubePRE single ended tube preamp (EUR 180). This is a tiny assembled and tested module (photo) without case or power transformer.
Reviewer Nick Whetstone had this to say of the semi-DIY project preamp:
As they go, the TubePre is as fine a pre amp/buffer as you will find for that sort of money. The build quality is good, and I like the little touches such as the inclusion of connectors for quickly connecting the inputs and outputs. No doubt there are a few improvements to be got from perhaps a different valve, and playing around with alternative DC blocking caps. But even as it comes, I am pleased to give the TubePre a hearty recommendation!
Check out the entire review.