I'm not sure what to buy, the DVX100 seems very reasonably, but i've seen some lowlight footage shot with the DVX that i did not like!!.. But all the other footage was great!! I don't know about the XL1s???? Good low light is very important for me, What camera has the best low light performance?

If low light performance is your goal, I think the Sony DSR-PD170 or the Sony VX2100 are the best in that regard.