@cstross (BE-4, right?)
I was looking up some quick stats, and it seems like each BE-4 engine is very close to SpaceX's raptor (around 500k freedom units of force). I don't know how much more power they can get out of a BE-4.
That being said, SpaceX is cramming 33 similar engines into one booster. I have no idea how -- I guess the 2 meters more diameter makes a difference.
I never thought I'd say this, but I am really rooting for Bezos here, to increase some competition.