El Cantante is damn good, but no best.

To add to that. Muchas gracias a mi pai, que es loco con la salsa y siempre taba escuchando salsa en la casa y en el carro.

Hector Lavoe - El Malo
http://www.youtube.com/watch?v=cT77krRcVIA
Good lyrics, nice sound.

Hector Lavoe - Che Che Cole
http://www.youtube.com/watch?v=XgId1N1UbLs
This one is so festive sounding and immediately catchy I think people who don't give a shit about salsa would even like it.

Hector Lavoe - El Dia De Mi Suerte
http://www.youtube.com/watch?v=qZK2wCpvwZg&feature=related
Moving lyrics, great rhythm.

Hector Lavoe - Ausencia
http://www.youtube.com/watch?v=ZG_WPfOiHYY
Emotional as hell and perfect

And if we're talking whole fania catalog...

Cheo Feliciano - El Raton
http://www.youtube.com/watch?v=1q4icTc0gOY

Ruben Blades - Plastico
http://www.youtube.com/watch?v=kCv7e_TNTnY
Exceptionally smart lyricist.

Ruben Blades - Pedro Navaja
http://www.youtube.com/watch?v=NdjEsbpWx9o
Pretty sure it was already mentioned. I think that'd definitely be in the running for best (and most popular) songs in the catalog.