I fly business class on ANA frequently to/from Japan. The difference between first and business is substantial. There are 8 first class seats in a large forward area that is larger than an area of business class that seats 14 passengers. Each first class seat is its own pod. Huge LCD video screens permanently mounted in front of each seat. Shelving system underneath screen has bedding (very nice thick comforters, nice pillows, etc). Seat turns into a comfortable bed that reclines 180 degrees (business seat does not).

Have never flown first, but I prefer to sit in the small two-row business compartment just behind the first class section. So I get to "observe" the upper crust . I would consider the upgrade for 30,000 miles worth it for a 13-14 hour flight.