Is flying from Frankfurt to Tokyo using Lufthansa 74H (747-800) good?

Hello!

I'm looking at a flight with Lufthansa in a 74H (747-800) from FRA to HND.

This would be the cheapest (1200€) route I could take for the days I'm looking for without 2 layovers. 1 layover of 1h50 in FRA. Pretty nice layover.

I'm also looking for the same date with JAL, using A351 from London to HND. Price is the exact same. But the layover in London Heathrow would be 7h! Pretty long.

Arrival from FRA would be 11am and from Heathrow would be 5:20pm. A full afternoon of difference.

Would it be preferable to endure that long layover in Heathrow + later arrival to get the A351? Or would the Lufthansa's 74H an already nice flight? I'm a bit torn between both.

Thanks for your help!