According to those who purport to know important things, Wagyu is in a whole different taste category than other beef. It's also become somewhat of a status thing and is priced accordingly. In the case of brisket there's certainly a noticeable difference (very tasty and easier to cook because of the marbling) but I don't think it justifies the price - at least not often.
I've only ever bought one (for an LTBBQ Gathering back when we still "gathered") and luckily a professional chef here on the forum cooked it before I could screw it up. It was excellent but didn't change my life - I'm still generally good with Prime (or even Choice if I'm desperate).
If you want to know more about Wagyu brisket, ask IR2dum. He's our Wagyu brisket expert, especially when it comes to dry-aging.
Turtle, thanks for recognizing my vast knowledge and expertise of dry-aging wagyu prime brisket. Most of you have all ready experienced this with me, but I feel that I must impart this knowledge of dry-aging prime wagyu brisket to the world. I can pretty much sum it up this way...DON'T DO IT! At least not the way I did it. Here's the embarrassing story that I had hoped would never be brought up.
It was a couple of years ago and it was almost time for our semi-annual Gathering at Backyard Jack's. I was trying to think of what meat I could bring to feed the 14 or 15 forum members and friends that will be there. There were a few videos on YouTube about dry-aging brisket so that was my choice. I bought the dry-age bags and a prime brisket. I bagged it, vacuum sealed it, and put it in the refrigerator for 63 days. Guga on YouTube did his for 63 days and I followed his instructions. It was timed to take out of the refrigerator, put in an ice chest with plenty of ice, and driven to Jack's house in Byron, GA to arrive on the 63rd day. We were all standing around the island in Jaxon's kitchen when we unwrapped this dry-aged brisket and started to trim the pellicle off it. It was hard as a rock and as Mike has previously stated, it dulled his very sharp knife (so sorry, Mike). I trimmed a little, Tim trimmed a little, Mike trimmed a little, and I think Turtle trimmed a little. When we finished trimming, there was hardly anything left. Maybe 5 lbs. And it didn't have a very pleasant smell. Not like dry-aged beef should smell. I made the executive decision to throw it in the trash so nobody would die from my handiwork. Probably my best decision. I believe everybody agreed and nobody died.
In retrospect, 63 days is way too long for a brisket. I'm still not sure what went wrong. Did I have a bag failure? Was it aged in the fridge at the wrong temp (34 degrees)? I guess I'll never know. All I do know is that I'm not going to waste a fine brisket like that again. Never again.
And just a little info on Wagyu Prime Brisket. It is available in Houston at Texas Star Grills and comes from Snake River Farms. Price is $7.99 per pound for typical 18 to 20 lb. briskets. They also sell Compart Farms pork. Regular Prime briskets at HEB in Houston is $3.59 per lb. average 15 lbs. Grass fed Choice Brisket at Kroger's is $2.29 per lb. average 13.5 lbs. Select grade brisket at Kroger's is $1.99 per lb. average 18 lbs.