First of all, to the haters: it's pretty ridiculous to get upset that TechSpot had the courtesy to poll its readers for their feedback. Getting "offended by the question" is childish. The folks who run this site and produce its content have a right to make a living, and if the ads aren't bringing in enough funding (perhaps b/c so many of us use adblock plus, which frankly is just common sense these days), they owe it to themselves to look for alternatives.
I value this site, and used several reviews to pick components for my computer. I also value independent journalism and content production in general. A lot of my favorite YouTube channels, like Scishow, now use subscriptions to raise the money needed to continue producing. This approach has ZERO effect on users who choose not to subscribe, which is exactly what TechSpot's proposal would do as well. If you don't want to subscribe, you get the same old site. If you do, you get access to a few additional features (mostly cosmetic), and the satisfaction of supporting a valuable project.
As for the actual details, I think even $3 is asking a lot for the offered features; at close to $40 a year, that's more than I pay for the couple of magazines I subscribe to that actually include physical copies in the mail 6 times a year.
Rather than appealing to the individual user/reader, try appealing to the community as a whole. Take the Subbable route, and talk about what raising additional funds would allow you to do for the site as a whole. Could you hire more writers? Provide more features? More frequent reviews? I'd gladly pitch in for a campaign like that--personally I'd probably max out at $25/year. But what would it get all of us, if enough of us contributed?