Hi
If you can afford it the 70D is the way to go the price has dropped and its a great camera with all the latest technology and very good IQ
forget the 50D i owned one , the 60D and t4i and t5i are way better IQ wise but not quite as robust
so budget wise a T4i is good value BUT go 70D if you can its great the IQ is improved noticable from iso 800 up in JPG over the 60D T41 and T5i
i went from 20D to 50D to T4i to 70D and 70D is awesome camera the new liveview AF is just stunning its great for Macro shooting with the touch screen system.. by the way the new touch screen system is just stunning from T4i on ,i wish my 6D had it as a camera i'd prefer the 70D but offcourse the IQ of the 6D is why i bought it i have also owned a 5D and 5D2 and 6D is best IQ by far i just love it just want the 70D tilting touchscreen and new AF system in the 6D i personally wouldn't want to go back to old technology and constant sensor screening and poor high iso performance !!