I had permission to talk to my parents as well. I was a convert of about 22 months when I went on my mission, and my parents were not very thrilled. If I remember correctly, they called the mission office or mission home once I arrived in my mission, and after that my mission president gave me permission. I was never thrilled with having this privilege because I hated being seen as not keeping the rules and because I wanted to keep the rules just like everyone else (yeah, I was one of those types). It certainly never distracted me, which was always the justification given for the rule against regular contact.
My companion's situation was similar. Except the part about feeling bad about it. Or keeping the rules.
My parents could never understand why I failed to thoroughly enjoy every single second of my mission. Probably because I was too intellectual or something.
I was on a mission in 1969 to 1971 in Italy. We could have called home whenever we liked, but it was expensive. You had to go to the public phone office or post office, give them the number, and wait 15 minutes for the connection to be lined up. Then they'd call your name and you'd go into one of 3 or 4 phone boxes, pick up a 10 lb. phone handset, and do that whole, "Hello? Hello?" "Yes, hello?" "Hello? Can you hear me?" "What? Hello? Can you hear me?"
Five minutes later you both decide you can hear each other, but at one US dollar per minute, you now don't have enough money to spend on a real chin-wag.