No more tapes?

I'm making the leap from tape to memory card... (obviously this is a techy post, so please only read on if your inner geek tells you to).

I'm just setting up the tapeless Canon XF305 (part of XF300 series).  I'm going to be filming a BBC documentary at a school over the next few weeks - it's the first time I've "gone tapeless", so if anyone has any top tips, please get in touch...

As well as switching recoring formats, I'm also (temporarily) abandoning Sony cameras.  I've just been messing around with the Canon to check settings and see what the picture is like.  So far, so good, but I've been told that it's not brilliant in low light.  It looks like I'm going to have to use gain a lot of the time, but I don't want the picture to look grainy.  I guess this can be solved by lighting, but if anyone has experience of shooting on the fly with this camera - particularly in ob-docs, where you don't always have time to control the lighting - please let me know how you got on.