Hello Andres,
But further benchmarks sound like a good idea.
I've started running some benchmarks with pgbench, with varying block & WAL block sizes. I've done a blog post on a small subset of results, focussing on block size with SSDs and to validate the significance of the figures found, see for more details: http://blog.coelho.net/database/2014/08/08/postgresql-page-size-for-SSD/
I've also found an old post by Tomas Vondra who did really extensive tests, including playing around with file system options: http://www.fuzzy.cz/en/articles/ssd-benchmark-results-read-write-pgbench/
The cumulated and consistent result of all these tests, including Hans-Jürgen Schönig short tests, is that reducing page size on SSDs increases significantly pgbench reported performance, by about 10%.
I've also done some tests with HDDs which are quite disappointing, with PostgreSQL running in batch mode: a few seconds at 1000 tps followed by a catch-up phase of 20 seconds at about 0 (zero) tps, and back to a new cycle. I'm not sure of which parameter to tweak (postgresql configuration, linux io scheduler, ext4 options or possibly stay away from ext4) to get something more stable.
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