This thread has really gone down. Whats with the bashing attitude? Seriously guys we are all grown ups, lets act like grownups as well.
Coming back to the topic, US equipment is the best to date and for me this is seen from the fact that even though US is a un reliable supplier when it comes to weapons, PAF still decided to go for the the block 52 even though we are well aware of the cons. We had the option for J-10 even back then when it was first shown to Musharraf. Now by saying this i do not want to sound disrespectful towards our chinese friends, i am just stating a simple fact from our side.
Every complex machinery is always prone to certain errors, that does not make it unreliable or crap like people are putting it to be. F-22 is something the rest of the world is yet to match. J-20 and PakFa are still in development. When they are fully inducted, God knows how many faults they will develop and will have to be rectified.