Hi Timo,
I received your book today. Wow, you have done well. The book exceeded my expectations, with no negative points at all. There are numerous period photos, all of which are printed in very high quality. There are also some really great shots of Type IIs, again in good quality.
Given that I cannot speak Finnish I cannot make comment on the main text. But the English captions are very helpful, especially to the modeller. The most helpful point for the modeller is that you have made comments on how the boat was changed and her colour schemes. The book is in chronological order, which helps to build the picture of the boat's various features and colour schemes. The colour side profiles also help enormously in this regard.
The 45 colour walk-around photos of the Vesikko are also essential. They provide a modeller with sufficient research material for a superdetail project.
Altogether it is a perfect research resource for a Vesikko build.
Well done!
Dougie