Good stills and good motion video are mutually exclusive functions, due to
video being an interlaced medium (motion edges will show "comb" effects
from the time offset of alternate scan lines) - you can minimize this
by selecting frames of moments with no motion from the interlaced video,
or by going to non-interlaced mode, introducing motion-blur in the
video (more in the TRV-900, since its progressive-scan mode gives 1/15th
second frames [the 30U gives 1/30th second frames] - so here again, you
would want to select frames from motionless moments [but the motion video
of the 900 would be more blurred due to the lower speed, and it is not
practical to switch back and forth while videoing, even if you are willing
to give up the times from videoing when you are taking stills]). I have
never bothered grabbing stills from either camera but the TRV-900 once,
and I did not like the quality, even in daylight, let alone low light.
With all the above, you still get paltry 640x480 digital stills that need
considerable work in a photo editor before being barely acceptable
for web use, let alone printout, unless your standards are VERY low...
I HIGHLY recommend a separate digital still camera for stills (better yet
is a cheap 35mm with a good fast lens [like an old Canonette QL-17, Minolta
Hi-Matic, etc. - or whatever you may now have...] with cheap 4x6" prints
from Fuji or Kodak 400-800 film, scanned on a $100 Umax 2100U scanner - with
quality level for under $200 that is FAR above what digital will give you...).
The Sony would require purchase of an additional WA, and one of the problems
I had with it (and partly why I sold mine and kept the 30U) was that I could
not find a WA that matched it very well (the other reason was the VF, but
for your purposes, the fold-out screen would serve well).
So, there! ;-)