another disadvantage is simply not getting enough light for anykind of exposure. Some (many) clubs have inadequate or virtually nonexistant stage lighting. Even at iso3200 and f2.8, I have a hard time getting the exposure I need on the proper speed to eliminate body movement on stage.
I can't stress this enough for those getting into dslr low light (concert) photography on the cheap:
Do not buy the combo body/lens packages. Buy a body (preferebly used, they don't hold the resale, however, good glass does) without a lens. Then, buy a lens. Preferebly a good quality pro zoom lens with a wide focal range. 24-70f2.8 is a good starting point. If you are on a serious shoestring budget, just pick up an fixed 50f1.8.
You will find, that the lenses that come with the packages will leave you wanting more, very quickly. Think of it like your taping rig. The glass is your mics, the body is your recorder. Quality glass will give you quality images (provided the guy firing the shots knows what he is doing). As for the body, new is not necessarily better, especially in competent hands. A 2-4 year old model body is going to be a heckuva alot cheaper than the newest model on the streets. For example, the body I shoot was around 1400 new. Today, they can be had for around 450-500, give or take 100 depending on shutter count/condition of body. It is barely 4 years old.
Glass is your investment. Good glass is spendy, but worth it. It will also hold resale very well (just like good mics will hold their value over time). A good body is spendy as well, but won't hold it's value (it's electronics) over time. For a pro, it is worth it if your firing 20k to 50k shots a year. That is their bread and butter and need a new body every year or so as they are wearing out the shutter and can justify the budget expense on a new body. For the average user, it isn't justified to spend 2-4k on a body that will be worth half that in 2 years and even less 4 years down the road.
Also, don't fall into the megapixel hype wars. Yes, megapixels are important, but most important is the the sensor. If your sensor is small (crop sensors), cramming more and more pixels on it won't necessarily make a better image. Often times it will make an image noiser or there will be more hot pixels. For example, on canon's 1.6x crop cmos sensor, canon keeps trying to cram more and more pixels on the same little chip. People are reporting that the images on their older, less megapixel cmos sensors are better and less noiser than on the newer ones with more pixels (think about the 24/192 audio wars. It's not necessarily about resolution on paper, but how well the converters <chips> handle the encoding). Plenty of 12 megapixel point and shoot cams out there, and I still shoot 8 on my dslr. The end result though, I'm going to have the better image.
Now on a full frame sensor, more is better. More space to put them there. I lust after the that new mark III
But can I justify 7k on a body? Not now. Need to sell MANY more prints for that
/rambling. Coffee is good, fresh snow on the ground, time to go out and shoot.