Hi,
I own both of these cartridges and have had a lot of time to compare both of them in my system. My turntable is an Oracle MK4 with Turbo power supply and a Graham 2.2 tonearm. First a little background, I have recently purchased a Clearaudio Matrix record cleaning machine and have started buying used records from a local thrift shop. I purchased the Shure because I wanted an inexpensive cartridge that I could use to play these records without fear of wrecking my beloved 7000FE5. And I had also read and heard all of the talk about this cartridge for years and frankly was curious to hear it. I have a couple of extra arm wands for the Graham tonearm so switching back and forth between the two is "relatively" easy. I also must add that in order to make switching the arm wands faster I added a piece of lead in-between the Shure and the headshell of the Graham. I meticulously trimmed the piece of lead so that I could switch arm wands with out adjusting VTF. I don't know if this added piece of lead is helping the sound of the Shure or not. I suspect it is.
Anyway first thing I noticed when playing the Shure was a slight increase in bass and this got me interested in making direct comparisons between the two cartridges. So here is the long and short of my comparisons on my system. The Audioquest has more high end and more high end detail. This is the one area that the Audioquest really outshines the Shure. After that the cartridges become very close in sound. I was amazed at how close a $300 cartridge could come to a $2,000 cartridge. The Shure is smoother and more enjoyable on many records. The Audioquest can sound great on some records and when it does the Shure can't touch it. But on other lp's where the sound with the Audioquest is a bit much the Shure smoothes things over and makes the music more enjoyable. I also think the Audioquest has a little better imaging. The Shure can be a little blurred in comparison. However I could happily live with the Shure in my system as the main cartridge. I have not found the Shure to be overly warm as some suggest. I find it less strident on some recordings. Overall the Shure is a really nice sounding cartridge and well worth the praise it gets. It really is a giant killer. It will make me think twice about purchasing a really expensive cartridge in the future. Just for clarification though. I am not saying the Shure is better sounding than my 7000FE5. What I am saying is that the Shure comes a lot closer to the sound of the FE5 than one would imagine given the huge price difference. Whether or not the difference in price is worth the difference in sound is a subjective matter. Some would say yes and others would say no.
If you are looking for a "relatively" inexpensive cartridge and want a taste of what some of the megabuck cartridges can do, I would recommend the Shure V15MR. It's a bargain.
P.S. I have recently changed all of the cables in my system to the new MIT Shotgun S1 cables. This change has made the difference between the two cartridges even greater. However all of the above is still accurate for my system, it's just not as close a race.