so ano ma-advice mo na mic sir kitC
Start with a known variable such as a Shure. The SM-57/58 didn't become a widely used mic for nothing, it had to sound good in the first place. Once you know the sound of an SM, use this as a baseline for other mic acquisitions. I, myself, have an SM-58, then I got an MXL V63M because it was cheap and based on other pro audio forums, it was an okay mic. Over time, I began to hear the MXL's quirks, like a relatively rough high end, but when we pitted it against a U87 it held up quite well. Think of the cheap condensers as a 'pang harabas' kind of mic and save up for the really good mics which you must pair with a really good singer.
Remember, in most cases, you have to match the mic with the singer. Just because you have a good condenser it doesn't mean that all singers will sound good with that mic. That's why most pro studios keep a variety of mics in their mic cabinet; even crappy sounding mics.