ratboy, I own and use most of the mikes you brought up.
Here is an overview of each from a "end user" perspective,
not an expert!
Studio Projects C1- Incredible "bang for the buck" large diaphram condenser. I need none/hardly any EQ on my voice with it for good results. (not suited for live performance-too sensitive)
Shure Beta 87- Punchy small diaphram condenser mike,
comes in two different models, supercardiod and cardiod pattern. (I have the supercardiod) Not as much detail as the C1, however, it can be used with good results for home recording as well as
live.
Shure sm57- A true classic (like it's fraternal twin the sm58).
On a lot of voices (like mine), it makes them seem more "rock"
in tone. Can't imagine not having one!
All three can work well with the tenor (or any range) voice.
If you can give them a try before you buy that's the best way.
P.S. the quality of your mic pre makes a big difference too!