I bought this device (VegaTrem VT1 Std. St. Steel) after viewing many videos of similar devices and by comparison it seemed the easiest to install with an enormous availability to maneuver the bending of the guitar strings.
Everything was exactly as described. It is a stable, solid mechanism that has no major problems in keeping the strings in tone. No modifications required. As a sustain, it looks a little shorter than the original Fender I had. It compensates by keeping the tuning and maximising free movement. It comes with four types of springs. The lowest tension springs are for the 0.8. I replaced the old one in about 15 minutes. I also use Fender Locking Tunners and a Tusk nut.
As for the Cons:
What I didn't find anywhere is the size of the device. I found that it is too deep (7mm) for the body of my guitar (Fender Squier) which is only 39.7 mm. The device protrudes from the body of the guitar by approximately 7 mm. So I'm a little disappointed with that.
I don't know if it's common, but the 6 blocks that guide and adjust the pitch are not the same. I received a set that contains three normal and three that have a bevel through which you can see, at the base, the height adjustment screws (at the saddle side). They seem to belong to another device model. Either one or the other.
I gave the maximum stars because the device makes all the money! For me, what he can do is more important than what he looks like.