Aerospike is dead now, low altitude ISP increase might revive it

[Radam]

Now the best liquid engine has 350 isp in vacuum. Aerospike should have something like 320 to 340 isp range instead of 290 to 330.

[NathanKell]

Have you tried flying on Eve?

That's not what aerospikes are for. Aerospikes are not "Iwin" engines that break the laws of physics by having the same Isp in vacuum and in atmosphere. Aerospikes are engines that have near optmial Isp no matter the pressure. You can never do better than optimal at a given pressure, but you can do a lot worse; bells are optimized for one pressure, aerospikes are 95% optimal at most all pressures.