We went with the SX5 instead of the SD5.
The SD5 (according to what I have seen in reviews) *only* records in HD. There is no option to record in standard def.
The SX5 will record to card in HD, or to DVD in standard def or HD.
I decided that since we didn't really know the impact of recording in HD only (and all the editing tools seem to just be releasing HD editing parts now, rather than it being a tried and trusted technology) we would go for the safer option and get the DVD/standard def option as well as HD.
The added bulk of the onboard DVD drive wasn't too much (or so I keep telling myself) and we would have to have lugged the stand-alone DVD drive around on our travels anyway.
One thing to note (per the early hands-on reviews) is that the battery is pretty clunky, but I can live with it. It is a different colour than the camcorder body and it it pretty big, but as long as it gives me power I'm happy enough.
I ordered from Circuit City - they have the option to have it delivered to the nearest store. So, if you know where you will be, that would be the safest and quickest way to order it. Best Buy do the same thing also. The advantage is that you don't have to wait around in the evening for the spotty person to see if it is in stock, etc . . . . it's just there. You could try http://www.bhphotovideo.com for a mail-order option.
Finally - you can't beat the value proposition. The US list price of the SX5 is $899 and the SD5 is $999 - some retailers are already discounting it slightly. The UK list is about £700 for both models, and the Irish list is €1,200 as far as I can tell. That makes it half price in the US and sure beats most camcoders you can get here in the €600 price range.
I'm sure I'm missing something, but I couldn't work out why the SD5 (without the DVD drive) costs $100 less than the SX5 - possibly because people will pay a premium for the smaller size.
I've just noticed that the SD5 comes with the burner - the early marketing stuff listed it as an optional extra (at a cost of $135 or so). That explains the price differential.
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