I currently own a G9 and I am looking to upgrade to a SLR for Christmas. I love my G9 for a take-every camera, but as I have gotten more serious with my photography I have become frustrated with its noise levels and poor low-light image quality. I have pretty much mastered all of the settings and functions of the G9 and I am looking to buy a camera I can "grow in to". I do a lot of travel photography, but I shoot plenty while at home and would love to start practicing taking portraits. I am looking to spend around $600 to start off with.
Right now I am considering two options: a used 30D or a used/new XSI. I have seen some pretty good deals on the XSI recently with holiday sales, and the features like live view and the self-cleaning sensor seem nice (and it uses SD cards. I know CF cards aren't that expensive but its just another thing to buy.) However, I do like the tougher body and top screen layout of the 30D (the faster FPS is nice but I don't really shoot sports or high-speed action much so its not that big a deal to me). As I understand it image quality is essentially the same between the two. My question is: do the newer features of the XSI outweight the semi-pro features of the older 30d ? Should I be worried about dust on the 30d sensor if buying used? I know this is mainly a ergonomics decision and I plan to go check both of them out at bestbuy, but I figured I would get some input from these forums as well. At the moment I am leaning towards the 30D because of the ergonomics.
My other dilemma lies with buying the lenses. One option is to get 50mm 1.8 and a 18-55mm IS and probably a set of cheap-o extension tubes to mess around with macro. That totals around 200 dollars if I get the 18-55 used. However, I am also looking at the Sigma 17-70 2.8-4.5 Macro. I like the extended range, small aperture, and macro capabilities, but it is more expensive than the other two (300 used, but I found this on craigslist: http://sfbay.craigslist.org/scz/pho/1496246400.html). Since I do a lot of travel photography I like the idea of having a decent all-around lens like that. Does it make sense to save up for the Sigma or should I just stick with the two canons to start with?
Thanks for your help!