Hi,
I was also deciding whether to get the inbuilt oven and microwave or just microwave with add'l functions for my future home.
I have decided to get microwave with multiple functions instead, just becos the price of the oven may not be worth paying considereing the v few times i will be baking. heheh
However, if you plan to bake (cakes esp) a lot and like once a fortnight, i say go for oven.
If not, i think it may not be worth the money.
We do tend to go crazy and buy stuff during renovation. heheh
Let us know what you finally decide