It's trivial that every country is after its own interests, but for what is worth, our short period of cooperation with the Americans during 60s and 70s helped us build a modern, well-trained army that saved our territorial integrity and sovereignty in one of the world's largest wars fought after World War II.
That aside, they also heavily improved our civilian infrastructure, education, quality of life, etc. When we had good relations with the Americans, Iranians lived in relative prosperity compared to what is happening now.
Our friendship with the Russians never achieved anything remotely similar to that. The Chinese were initially helpful, but it all changed after their focus shifted towards Arab states in the Persian Gulf. We haven't had normal relations with China ever since, even though our interests align and we aren't enemies at the moment.