I just got Echoes, and I must say, Master Chief can suck it.
The game itself is much more difficult than Prime. The new foe of the game are the Ing, these bastards put space pirates to shame. It took me 2 or 3 tries to get past the first boss, in Prime retrying boss fights was almost non-existent.
The majority of the game is Prime with a heaping of polish and a few new bits added on, some people might not be enthused by the lack of radical change, but Prime was so farking good that it didn't need much to be improved on anyway.
I give it 4.5 out of 5 lobsters.
The only thing that hasn't satisfied me is multiplayer, a throwback to games like Goldeneye 64.
Oh yeah, I forgot.
All your bees are belong to us. Never send a man to do a womans job.