Nick_C wrote in post #4134986
XTi, why? well I personally think a backup should be fairly small & lightweight, its also better spec over the ageing 30D.
Only in terms of megapixel count. If you do a side-by-side comparison of the XTi and 30D specs I don't think the XTi wins in any way except for megapixel count, dust-cleaning system, and less weight if that's your thing. And definitely not if high ISO noise matters. The XTi is roughly a stop noisier than the 30D according to reviews I've seen such as this one
(a 40D review, but scroll down to the comparison photos against the 30D, XTi, and 1D Mark III), and it wisely doesn't even attempt ISO 3200 like the 30D does. It would have to be a 30D for me.