Ive had 2 Slides since they were available. I have concerns about their capability to hold heavy weights in place. Both mine, and my mates 2 tend to slip to their full length very quickly when used with heavier gear and walking around. This seems to be due to movement making them loosen. Just pulling on them doesn't give any movement.
Saying that, i love the feel of them and continue to use them (also have a Leash and Cuff). In fact a couple of weeks ago i brought the Slide in Blue. It looks lovely but the padded part that goes across the neck seems a stiffer, and is difficult to get in my bag. Im hoping it will loosen up very quickly.
Not sure about the Slide costing £80 from Park, as i got mine for £54 and thats more expensive than the standard black ones.