I love this whammy bar! It works really well.
I installed it on my Gibson SG special.
I do not have de-tuning problems, even if I bring it all the way to the body (though if I do it repeatedly it might detune a bit). I am using 10-46 elixir nanoweb guitar strings, but I have also used ernie ball 09 slinky strings, and did not have any problems. I do use some nut lube though.
It also fits easily into my existing gig bag and hardcase.
However, there are some things to consider with this device.
On my Gibson SG special it does not fit entirely, it was off by 0.5mm, I thought I had measured it properly, but apparently not. To make it fit, I used a file to grind the bolt holes slightly larger, until it fit. Next, the pickguard of the SG is in the way of the plate under the spring, so you need to make a modification, either by cutting the pickguard, or by inserting another pickguard underneath the plate. I opted to make a mini-pickguard that matches the shape of the underplate of the les trem.
One last concern is the bridge height on the SG. If the bridge height is too high (and on the SG it often is, since the neck sweeps backwards behind the body), then it is possible for the strings to touch the bridge as they go down towards the les trem. Therefore, raising the les trem may be necessary. For this the pickguard and the washers help.
Despite the issues I had installing it, I did not need to make modifications to the guitar at all, and I love the sound. 5/5 would buy for all guitars with stoptail.