Hi there
Sadly, we haven't yet reviewed either of those particular models - though both companies have been producing some impressive systems lately, so they're definitely worth a look.
Other options could include Sony's DAV-DZ410, which scored four stars back in May. It's an impressive sound and vision package - with the tall speakers you're after - but inexplicably lacks an HDMI-output: though its component video perforrmance is excellent at the price (you can pick it up for around £330).
Another strong four-star package is Pioneer's DCS-360, which offers great pictures via its HDMI output, though isn't sonically the very best (though still good for £300!) via its Tallboy speakers.
Hope this helps. Anyone seen/heard the LG or Samsung systems?