i was also considering an iMac over a PC. Made the mistake of buying a dell (similar to what you are considering). the card readers didn't work, and despite the fact that i told the dell support staff that it didn't appear that the card drive was installed properly (was shaking, not in place firmly), he had me rebooting around 5 times, and trying other things b4 getting me to open the casing and finally after 1 1/2 hours said that it looks like there may be a loose screw!!!
he recommended that i wait for Dell to send a replacement screw which i could replace the "faulty" screw with.
i sent the system back and am looking to get an iMac as well. However, bcoz of a trip i'm planning through the southwest, i will probably need a laptop more immediately. I wanted to get some advice on an Apple laptop i could get (iBook??), that could run photoshop, do raw file processing in the field and.....and this is the clincher be relativley affordable (i'm hoping to only spend around $1200-$1500).
Is there a mac laptop that would meet my needs? How much Ram is needed, and how large a HD would be recommended? (how much free space would there be after the operating system and other software requirements???
once i do get an iMac, will it be seamless switching back and forth between the Laptop and iMac (same operating system on both?)