Tim, I got a pair of A520's by mistake for my girlfriends bike. Like you, she hated them. But I didn't want to send them back to England. I gave her my pedals Shimano 770 series and she loved them. I inherited the A520 and actually I am ok with the A520 and the one sided cleats. I don't have to wear my bike shoes, to go shopping or to eat. What do you like better about the A530's?
Addressing the original post from Sanuk, I like cleats that have good float, I can walk in, and now in my later years I like a pedal where I can wear my sandals to ride in and my flip flops to go explore, dinner, or grocery shopping. So if Tim likes the A530's I second it. (because I just completed a 225 mile 3 day and the A520 were fine for me) Some people like double sided pedals to start from a stop with a loaded bike. I am ok with a single sided pedals. Make sure you get a 30 day return and I might get them from Bike Nashbar who has a good price.
My ex had the Shimano M424 I did not like it as a serious pedal. It is kind of like a training pedal for someone who does most of their riding on the non cleated side. I would think that if you want a pedal to start with, it is safer to go with one that is two sided. It would be nice if they could have a slight recess, of the cleats which would make it a true multi purpose pedal.