Actually devs and not moochers of iOS7 think iOS7 on their current iPhone works great. The ones who tend to complain are people who get the betas and are not devs so they can't even install it properly.
While I, too, think iOS 7 works great on my 5, this is not a subjective mattermuch was made of how, though A6 was not the most powerful chip around, Apple's 'handmade' architecture allowed it to be the 'Goldilocks' chip for then-current iOS 6. To hear it from AppleInsider, it was a triumph of efficiency:
http://appleinsider.com/articles/12/09/21/first_look_inside_apples_new_iphone_5_a6_chip_appears_to_show_3_gpus_2_cpus