SpaceX just teased a photo of its highly anticipated Falcon Heavy rocket

I look forward to the first launch of the Falcon Heavy and wonder a bit about the complexity. I get that 27 engines is a lot of engines, but the N1[1] experience was from before we had decent computers and materials technology. Today how much less reliable are 3 Falcon 9s than 1 Falcon 9? (I know 6x (n!) higher risk).

So three F9's, they all have to come to full power at very close to the same time to avoid stressing the rocket frame or the launch pad too much. At which point they need to burn fuel at a co-consistent rate so as not to move the center of gravity of the rocket too far off center. Then how do you land those boosters, can't really land next to each other on a landing barge.

A lot of deltaV though, very big payloads into orbit.

[1] https://en.wikipedia.org/wiki/N1_(rocket)