Warthur
Rush's Feedback EP was a little something they put out to celebrate their 30th anniversary. There's not much that's very proggy about it, and that's intentional - they're just doing cover versions of songs which influenced them when they were starting up, and that means bluesy hard rock is more or less the order of the day, with some doses of psychedelia and garage rock on the side.
That said, the Rush of now isn't the Rush who put out their debut album - Neil Peart wasn't in the band at that point, for one thing. For another, Rush on the debut album were largely ripping off Led Zeppelin, whereas they're able to capture the spirit of a wider variety of acts here. They don't try to mess with what works, but they don't try to mimic the originals slavishly - it very much sounds like a well-honed group of musicians doing great covers of fantastic 1960s songs. Don't go in expecting any prog epics and you won't be disappointed; take it on its own terms and it's 27 minutes of pure fun.