I won't exactly add any important information here, but as I've mentioned before,
my old teacher has been over to Martin's place and tried the various basses. What was then attributed to Maggini is now attributed to da Salo, but the one he fancies is the Joseph Panormo. Apparently, both are extraordinary instruments, but the Panormo was just a bit more accessible. He'll go back and make up his mind in the end of this month, I believe. But now, there's also a Hieronymous Amati thrown into the picture... the plot thickens.
Point being, that a good Panormo is most likely as good as it gets.