想買部數碼相機，SONY DS R1 如何？

You mean the DSC-R1 right?

This one is 2005 technology, and probably not many stores still carry them. Also, the lowered prices of more REAL digital SLRs has made this piece obsolete.

It does come with some nice functions. But its bulky body design is IMO a big minus.
Read the review here:
http://www.dpreview.com/reviews/sonydscr1/page27.asp

I suggest you look into other alternatives.

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