I have the Slide and am really enjoying it for heavier setups where the width of the strap helps to distribute the weight of the camera/lens. My review is here:
Peak Design Slide reviews - Pentax Camera Accessory Review Database
As @colonel100 indicated above, there's also a good discussion of the Slides and Leashes in the thread he linked.
Rumor has it that Santa is bringing both the Slide Lite and the Leash down my chimney, so I'll be happy to share my impressions then. I asked for the Lite, in particular, because the Slide can be a little over the top just going for a walk with a small kit.
I'm with you about the neck thing. Ouch. I really like the way the setup on the Slide lets the camera hang just right at my side. And it really does "slide" easily up into shot-taking position. I can't imagine the Lite would be any less useful, perhaps more so with less bulk.