Why Merlins sound better then Sonus Faber

Sounding "better" is completely subjective. Everyone has different ability, interpretation, and preferences of what sounds "best". So, if you think Merlin sounds better than SF, lucky you! You get to save 5x the amount of money. Go buy music with your savings!

I guess I meant to say more transparent, closer to the original recording without adding anything else. Unless I am wrong?

Unistar, music is so subjective so its always impossible to say anyone component is better than another, regardless of price. Some people like the Sonus Faber sound (I being one of them). Some people love the resolution and speed of Magico, others think its too sterile. As rockadanny said, go have some fun with the money you saved!