Longely I have switched the beta and am having a much better experience.
As far as the preview feature being default behavior. No other browser works like this. Without knowing it was there I thought there was something wrong with my trackpad and restarted it several times before switching to mouse and eliminating that hardware. I then unplugged all my keyboard periferals in case of them them was sending a stuck keypress, then rebooted my machine to make sure there wasn't something wrong with my computer before realizing it was only happening if I was using Orion as my default browser.
I want to say again, that I do like the feature as an alternate behavior like it is for safari hard press, I could see using it with control or command depressed, but for that to be standard left click, it breaks a lifetime of expected behavior when simplly left clicking a link. It also represents a conflict between the behavior of clicking links inside Orion and outside Orion. I doubt you want to have the preview coming up anytime you click a link inside the Orion browser. I can't pretend to know how others will feel about it, but for me (especially without very clear communication), it feels extremely broken.