I suspect it will be cheaper to use a toaster rather than having to spend a long time heating up the grill. Also the toast pops out when it is ready. And our toaster (at least) takes varying widths of bread.

Our cooker has gas burners and two electric ovens, so it sounds quite similar. The top oven isn't really much use as an oven as it's a bit underpowered, and the bottom one is a fan oven so it cooks things better and faster. At least the knobs are labelled in centigrade. I guess you will have to work out the right settings for bread.