I have the C3 now, I had a C1, they both sound the same in cardiod pattern.
The C3 has the benefit of being multi patterned if thats what you are after.
I also have a TLM103, on MY voice, the C1 and C3 sounds better, thats not the case with every voice though.
The C1/C3 are very good value mics...and I am very happy with mine.
I have never used a U87 so cant comment.
I would say this, any mic, regardless of manufacturer or price tag, will not suit all voices over all other microphones.
If you find a mic, that you like, for your voice, and you can afford it, buy it and stop searching...8)....
cheers
Wiz