In December I ordered the Dawes SST (not AL, steel). I've been riding around 250 miles a month. I clean/lube the chain every 200 miles or so. I don't do maintenance other than that, really.

How long does it have before something goes wrong? What will be the first thing I have to replace? I'm new to bike maintenance and I'm not sure what all I should be doing, so tell me what I'm doing wrong (other than telling me to buy a Kilo TT). Because this is a low-end bike from BD, is there anything I should be especially worried about?