Can microwave with convection replace an actual oven?
Yes, this could replace an actual oven, because it is an actual oven.

According to the specs on the website you linked to, the convection element is completely separate from the microwave element. There is a "microwave mode" and an "oven mode."

The only negative I see is that the heating element is 1600 watts. That's not a lot for that size oven. Toaster ovens typically run 1000W-1500W, and full size ovens run as much as 2400W. That being said, it just means it might take a little longer to warm up. It's not that big of a deal. And with the convection happening, heat will fill the cavity just fine. It just might take a little longer.