the canon 550d , 600d , 60d , 7d all have the same image quality... so does it make the 7d a looser infront of the cheap 550d? NO.
same way y would ppl get nikon d7000 when you can have the same image from the cheaper d5100?
the problem comes when you want the pro controls in your hand... how will you compose your shutter speed / aperture / iso with just 1 split of a sec on the nex 3 or 5 ?
do you think the built in computer has a better vision then your eye?
do you think a 3" lcd has better sharpness then you own eye vision?
these are a few problems and questions which comes when you come to compare a true dslr against a hybrid like nex 5 which gives you quality of a aps-c sensor but the controls are like p&s.
if you are really serious about your pics and want full control, get the DSLR....
Expensive cameras have a top LCD and are much bigger in size.... they also have more buttons ..... so you have quick controls on your fingertips...
image to change SS/AP/iso i have to scroll through menus then adjust... and if its not right then again go to menu and adjust..... and with all the artificial enhancements on pics, the originality is all gone way b4 u get bak home.