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First of all, in my view you should only consider this camcorder if size is quite important to you. Due to the Sanyo Xacti's small size & slim profile (fits into even a small pocket easily), I believe it's unfair to compare the Xacti directly to bigger camcorders that have more room to include better optics etc.
Video quality: Quality is good outdoors during the day in fair conditions. If you're going to do most of your shooting in such conditions, you'll be fine with this camcorder. It should be noted that the Xacti has a very small lens compared to proper camcorders and thus won't capture as much light. As a result, in low light and indoors, quality suffers massively and the image is very grainy.
Still photos: I tested the still photos feature indoors in decent light, and unfortunately it's very poor - worse than even a mediocre mobile phone camera without flash. Don't bother using this for stills.
Build quality: Unfortunately the build does feel a bit tacky in places, yet it seems sturdy enough and I wouldn't worry about it breaking even with rough handling. I should note here that the lens cap is a bit dodgy, it can be difficult to get it to click into place sometimes.
Accessories: Considering this is a Full HD camcorder with a mini-HDMI port, I think it was quite poor for Sanyo not to supply a mini-HDMI to full-HDMI cable. People typically don't have such cables lying around (unlike normal full-HDMI cables) and it's the only way to output Full HD video directly to a TV. It wasn't a big deal as such cables are available for a couple of pounds, but this makes the lack of inclusion even less excusable - I didn't even realise this type of cable existed before I read about it in the manual, and I would usually expect such a cable to be included. The component cable supplied can't handle Full HD.
It was a bit difficult to decide whether to give this camcorder 3 stars or 4 stars. If you're comparing it to proper camcorders on image quality, even 3 stars is difficult, but then - as I mentioned at the start of this review - such camcorders are much bigger, heavier and pricier, so I don't think such a comparison would've been fair. Considering its size, I think a comparison to good quality phone video cameras - such as that on the iPhone 4 or latest Nokia models - is fairer, in which case the Xacti generally comes out much better (except possibly in low light!). For the afore-mentioned reasons, and as I think the phone video camera comparison is fairer, I have given this 4 stars.
In conclusion, this is a decent choice if your mobile phone's video camera isn't good enough for your needs, but you don't need a fully-fledged camcorder, and want to retain phone-like portability.
I have also reviewed this on Amazon under the name M. Marikar