This season I have decided to start learning about fin adjustments. I have Fin Whispering, which I am looking forward to reading. That said, I am going to need a set of calipers. What do you suggest? I looked on Performance Ski's website and they have one from Radar and one from D3. They look similar, but the D3 calipers are $30 more. I want to buy a nice caliper that is going to last a while.