In USA, Sanyo recorders are sold under the Yamaha label. The
PS603RM looks like it uses the design of the Yamaha Pocketrak 2G.
(The 2G has two mics.) I agree that this form factor is almost too
small to be easily operated by someone with adult-size fingers.
I was skeptical of the MicroSD cards, too. But when I took a look
at the Yamaha Pocketrak CX a couple of months back, I found that
the MicroSD card worked well. The CX has a push-to-release slot
for the MicroSD, rather than the tight-fit-grab-with-tweezers slot
found in cell phones. So i's easy to install and remove the MicroSD
card.
ZipZoomFly and SuperMediaStore offer a Sandisk 8GB MicroSD card for
$33, shipping included. The package includes an SDHC adapter so you
can insert the card into a typical flash card reader.
The Yamaha Pocketrak CX is larger than the 2G, and also has quieter
preamps. But it's not in the same league as the R09HR, Olympus LS-10
and Tascam DR-1. My guess (and it's entirely a guess) is that the
Sanyo with 4 mics will also be an underperformer when it comes to
sonic quality.
Flintstone