I've been asking myself the same question but decided to go ahead and order some dollars with Crown last night. I was tempted to hold on but past experience over the last few months has shown it to reach the 1.50 mark and then crash again so I'd be kicking myself if this happended & time ran out for it to rise.
I'll be changing more money before June so fingers crossed the rate still improves but I feel better for changing what I've got now at 1.5050.