I will qualify this by saying my only experience with them has been at the Foodie Festival.
Everybody was raving about Fukuburger and when I saw their truck I had to try it. We ordered and then waited over 40 minutes to get our burgers. I would say, well its a food festival and its busy.. but it was 3PM on Sunday and there were a total of 5 orders ahead of ours. It took 40 minutes for them to serve 6 total customers.
So after the wait, we get our burgers. For the price of $7 a piece, I was disappointed straightaway. The burgers are very very small. The bun is the kind you buy in a pack of 8 for $2 at the grocery and I will be generous and say it was 1/4 pound of meat... but I doubt it was that much. Now I will say the flavor of my egg burger was good... but both my and my girlfriends spicy burger were both cold. Like cold bun, cold meat, cold toppings... everything was cold. It took 40 minutes to prepare a cold burger. Ordinarily, I would have just taken it back. But in that 40 minute wait time, their line was now really big and I didn't want to stand in line 10 more minutes to wait 40 minutes on another burger.
I was really disappointed and it makes me sad. I really love supporting my local Las Vegas businesses.. but I won't be back to Fukuburger.