I have to agree with Beaglebuddy, I've used the exact same idea with the Dakine protector over the Neil Pryde one as soon as I learned that the velcro on the Pryde sucks. I also have the NSI nose guard on most of my boards. It's very nice and looks pretty good.
I'm no expert and have been windsurfing for only about two years. The padding has saved my boards on quite a few occasions; maybe even the mast and boom. Even though I can now predict when I'm going to be overpowered and keep in control, I still use them. They don't hinder my gybes or water starts from a 4.0 to a 9.5 and EASE my mind when trying new things. The ten screws in my leg from mountain biking are what usually puts me off.
I installed the NSI protector using silicone caulk. It's not as strong as the epoxy and it's easy to remove. On one occasion I had the boom smack the nose into the pad HARD and half the pad came off (unglued). I had to put the pad back on but it gave me an opportunity to check the board status.
Sure, it's a little bit more weight and the "cool" windsurfers won't get it.
You can still learn how to repair your boards; just go wavesailing. These pads don't help worth a crap there. Though the extra pad on the extension will help a little when the longboard/sup tumbles in the break with a big sail.
Could have used a larger size NSI protector on this board but the curves make it hard to adhere.
BTW if anyone's wondering what's in the Dakine pouch on the harness: ACR Resqlink 406 PLB, set of prescription water goggles (in case I loose glasses), some downhaul rope.

flame away!