Hello Ross
This is no answer, I'm afraid...
....it is a great shame that there is no easily-accessible ( that I know of ) collected source of good, contemporary reviews. If I have the foresight, I cut out and keep reviews of books which are likely to interest me.
The Sunday papers and journals such as
Literary Review publish excellent reviews when these books are published ( from reviewers such as John Keegan, Richard Overy, Stephen Bungay etc etc ) and it really does seem that many of these very useful reviews just 'vanish from sight' as soon as the newspaper is thrown away.....