FWIW: I'll testify to (on windows) the portability of PostGreSQL; the competence and helpfulness of the support (including Win32 issues!); the usability of the graphical tools; the completeness of the implementation (triggers, cursors; stored procedures (including the ability to write them in Perl)); simple and fast (binary) install/uninstall.

I did have some trouble compiling DBD::Pg at one point (circa 5.8.5), but even that was bypassable because of DBD::PgPP. I had no problem building DBD::Pg for 5.10 64-bit or 5.8.9 32-bit.

I don't have much occasion to use it, but when I have, it has been a pleasure.