Okay, I've been using it for two hours now. Here's my take.
This works great on sites that it prefetches (such as google and other major search engines, ebay, craigslist, etc) as that is what this plugin is designed to do. Since the links are prefetched, you get an instant preview of the links. And you can use the scroll wheel to go from one search result to the next. Within the preview, click on any blank area (the "white" area which is not a link, form, drop-down box, etc.) and your original window will navigate to the link that you are previewing. Within the preview, right-click on any blank area and the preview will close. You can also close the preview by moving the mouse out of the preview.
On the sites that are not prefetched, this plugin is pretty useless. To get the preview, you need to hover over a link causing a small lightning icon to appear about 1/2" above the link, then you need to move your mouse up to hover over the lightning icon (if you miss, then the icon disappears and you have to go back to the link), then you'll get the preview of the link, then you can mouse out or right-click to close the preview. My old way (shift-click to open the link in a new window, ALT-F4 to close that window) is still faster.
Here are my major complaints about this plugin:
* Having to hover exactly over the lightning is a nuisance, especially on sites that aren't prefetched since you have to hover twice (once over the link, then over the lightning icon).
* If you accidentally mouse out of the preview (which happened a LOT), that causes the preview to disappear.
* Any click or right-click within it will cause an action. You have to very gentle with the preview, otherwise it'll go away.
* You cannot open links in new windows from previews.
* The preview apparently cannot play certain media such as the imploding videos found on links in this thread
* You can manually select links to prefetch, but AFAIK, that's only on a link-by-link basis. You cannot select an entire domain (like dvdtalk.com) or subdomain (like the Tech Talk Forum) to be prefetched. For example, to prefetch the threads in the Tech Talk forum, you have to right-click on each thread and select it to be prefetched; you cannot choose all the threads in this forum to be prefetched with a single command.
* The prefetching uses up a lot of bandwidth and a lot of hard drive usage. Whenever I do a google search, I hear a lot of HD noise since it's prefetching all the links in the background. I can hear the HD jiggling for a good 15-20 seconds after each google search. The same goes for craiglist or ebay. Every time a page loads, the HD goes nuts for a good 15-20 seconds to load all the other pages. It's good for instant previews, but it's also eating up unnecessary bandwidth as well as wearing down on your HD.
I'm gonna keep using it for now, but only on the sites that it prefetches by default. I won't be using it on other sites as it's more a nuisance than it is a benefit.