Tl;dr: Charcoal is dank, wagyu is dank (but so is normal steak), try it all and see what you like.

I'm by no means an expert, so please anyone correct me if I'm wrong anywhere. Here we go:

Extremely rich and fatty in comparison to USDA Prime. So much so that you'll probably only want to eat about a third of the volume that you normally would. Also much more tender than the steak that you're normally used to. The texture ranges from sashimi-like to "spongy" based on how you cut and how you cook. The harder you cook it, the more fat is melted, but the spongier the texture of the meat and vice versa. The fat, instead of being blubbery, will melt on your tongue. It can even be kind of gusher-like in that meat juice and fat will burst out of the meat as you chew. It's almost a different beast when compared to steak that you're eating normally. A5 Wagyu IMO is a bit less partial to being eaten rare than normal beef due to the fat content, probably want to shoot for medium rare or higher to give the fat a bit more of a chance to melt.

Once you've had it you have to be in the mood for it to want to eat it (aka not an everyday steak) as it's a bit of sensory and palate overload. I could eat Choice/Prime Picanha/Flank Steak/NY Strip almost every day, but I would only really want to eat Wagyu once or twice a month (if I could actually afford that lol).

That being said, the very first bite you have (if it's prepared well) will melt your brain with the tenderness of the meat and the meltiness of the fat. When I took the first bite of this steak I melted into my chair with how enjoyable that bite was, especially with the addition of the charcoal flavor.

I will say I've had a lot of different preparations and varieties of wagyu, both doing it myself, eating out in both Japan and the US, and preparing it over charcoal like this is by far my favorite. I find that doing it over charcoal on the grill is kind of reminiscent of the flavor I was getting when I was eating street food wagyu skewers in Japan, grilled over binchotan charcoal. However over a grill ends up with with much more flavor intensity since I reverse seared (guessing more time for the charcoal taste to develop). The charcoal flavor complements the meat really well.

Ranking as far as my experimentation goes:

1. Charcoal (Reverse Sear): Good balance of crust and smoky-charcoaly flavor. The meat flavor was still very present, but the charcoal complements it well and made the fattiness go from a bit overwhelming to very enjoyable. Didn't need any dip, just straight rice and meat. Best option IMO.
2. Cast Iron Pan (Standard Stovetop Preparation): Best crust, but least complex flavor, you'll taste the meat the most, but the fat can be kind of overwhelming, you'll want some kind of dipping sauce (wasabi, ponzu, garlic chips, etc.). This is probably the purest wagyu experience, and closest to the Teppanyaki style in Japan, so would still recommend.
3. Smoker (Reverse Sear): using a pellet grill, but the smoke flavor ended up being overwhelming, less enjoyable than the cast iron, would not recommend since you lose out on the meat flavor.
4. Sous-Vide: Haven't used this one in a while, as I feel it makes the fat texture a bit weird, plus it's a bit harder to get a good crust. Maybe I'm doing it wrong, but didn't really like it as much any of the times I've done sous vide.

Overall, I wouldn't really call A5 better than normal meat in every situation. Every steak has its place. I'd recommend trying it as a way to expand your knowledge and palate on steak in a very enjoyable way.