I've cropped about 25% of an image from my Oly, had it printed at 20x30 and unless you were pixell peeping, all the digital grunge that was present got lost in the bokeh. It is a compact, but it has an f1.4 lens.
The Sigma is a DSLR, and with L-glass can produce some incredible images, but it is a cranky, crotchety beast that requires buckets of light, don't even think of shooting over ISO 200.
The 60D doesn’t have the Foveon “look”, but it has allowed me to capture images in several situations where I wouldn't have even gotten off a shot. I can take descent pictures at ISO 800 handheld that with the Sigma requited a tripod and auxiliary lighting.
As far as prices, you should get several thousand images out of a camera body. Your real investment is in the glass, which locks you into a particular manufacturer's system unless you want to get involved with adapters that let you use lens X on body Z at some time in the future if you decide to change.
Finally, consider the total cost of a camera system. Yes, one or two thousand dollars is a pretty good chunk of change, but over the course of ten years that breaks down to $200 per year or a little less than four dollars a week,
and while you do have costs associated with printing an image, I can get a 16x20 print on matte Fuji paper done on a $4000 Epson printer at Sam's club for under $10, and you have 0 costs for film.
This is truly a golden age for photographers and modern technology allows even a rank armature to produce pictures that equal and even surpass works of the Masters of times past. Part of the process and part of the fun is just the learning process that results with picking up even a cheep $100 camera and being able to shoot hundreds of pictures for free, and in the process, learning by doing.
I am dreaming about a Fuji X Pro1 with all three lens. I’ve tried to convince myself I’m too much an amateur to really justify it but I still want it and an A5 convertible.