One of the few shops local to me carries the .38spl Nyclads, and I bought a box for use in my RG40. The accuracy is about as good as any other 125-130gr round as far as I could tell, and they pack plenty of punch for a non +P defence round. In my initial testing using modeling clay, the bullet opened up nicely, especially considering it had come out of a 2" barrel.
I just recently got to test it again using some home made ballistics gel (close to ordinance gel calibration, just a bit softer), and was disappointed. Though the bullet made it all the way through about ~18 inches of gel and into the backstop, it failed to expand, showing just a slight flaring at the mouth.
Obviously, penetration trumps expansion, and I am confident that this round would still be a good stopper with proper placement, but if what you are looking for is a round that will reliably expand at lower velocities, you may want to look elsewhere.