I guess I'm a minority here, but I would swap out your cardioid mics for omnis since you are just getting started.
Here's why. Cardioids are directional, which means that if you move around at a concert, or turn them away from the sound source, you are going to get a big change in volume. Omnis are a lot more forgiving and--bonus!--give you more bass than equally priced cardioids. If you record outdoors, omnis are also less susceptible to wind noise. (Though the ones I'm going to recommend come with windscreens anyway.)
I've made some very nice recordings through the years with Sound Professionals BMC-2 omni mics, which are eraser-sized and can be clipped to a shirt collar, hat, or whatever, plus a battery box. SoundPro actually just upgraded the elements that go into those mics, and the newer ones sound appreciably better. They are sensitive enough so that you can get away with just using a battery box, no preamp; if you are recording a really quiet concert, just go straight into mic-in instead of line-in.
Oh, and save a little money and skip the bass roll-off. Truly crushing bass will overload the mic before the signal gets to the battery box, and otherwise, line-in can handle it. You want to get the most accurate recording the mics can give, bass and all; if you want to lower the bass, you can do that on playback.
I have just gotten some CA-14 mics and am looking forward to recording with them, but if you are watching your budget and want instant gratification, the SoundPro BMC-2 and a battery box would be an excellent starter kit. Get the clips with the BMC-2, and get the extended warranty if you are going to be using them a lot, since they are on thin wires (great for stealth) and can wear out before three years. SoundPro's customer service is excellent, and you'll get replacements fast.
And if you can afford the extra $$ for the recorder, the Sony PCM-M10 is just a joy.