On every U2's forum I've visited, before or then comes the time for a topic called "Bono vs. Freddie."
There are many U2 fans who prefer Freddie's singing, but there are a really few Queen fans which prefer Bono.
I have to say that I love both bands, maybe U2 a little more (but in my teens I used to hate them and really love Queen instead).
To compare two singers like Bono and Freddie is hard, primary because their voice hasn't been the same all over the years.
Bono voice has at least six different periods. I mean from his vocal timber point of view.
1) Boy-October era; 2) War-Unforgettable fire; 3) Band aid - Rattle and Hum 4) Achtung Baby - Million dollar hotel OST; 5) All that can't leave behid - How do dismantle an atomic bomb; 6) No line on the horizon - nowdays
Freddie Mercury had 5 different vocal shapes:
1) Queen I - A day at the races; 2) 1978 - 1980; 3) 1980 - 1986; 4) The Miracle - Barcelona; 5) Innuendo album and out takes for Made in heaven
About Bono, I prefer Bono's singing in Band-Aid Rattle and Hum era, Achtung baby era, and nowdays era. Nowdays he has even learnt to sing properly (I mean his technical skill is good).
About Freddie, I prefer Freddie's singing in 1980-1986 era, Barcelona album (but not the Miracle), and just a couple of songs on Innuendo (for example The show must go on... but on that album his voice got generally "thin", I guess for the desease). People use to think that Freddie was a real technical singer, but he wasn't. He was just pure instinct like Bono was until he begun taking lessons when his voice seemed to be gone. They say Freddie never took vocal lessons (as Bono in his prime... though I think sometimes singers tend to hyde the truth, I don't know why), so you cannot say his singing was techical. Talking about himself, Freddie spoke about his envy for singers like Rod Stewart who had a better technic and took lessons.
About Bono vs Freddie, here's what I think.
Though Freddie's voice had a better range than Bono's, maybe even more power (but Bono's singing in his prime was really powerful), just by little I prefer Bono's timber and interpretation.
They are my two favourite singers of all time. It's hard to say who I prefer. Maybe Bono wins just by a little (50,1% vs 49,9%). I don't mind about range or technic, I'm talking about vocal-timber and interpretation.
(sorry for my English, guys)