Baking Adjustments When Using a Countertop Oven
I've found that smaller ovens do tend to crisp the top (or bottom) more quickly, as the heating element is closer to the food surface. 

For scones, you may want to 


prepare it in smaller batches, 
lower the temperature by a few degrees, and crank it up for the last 3-5 minutes to get a more even bake and better cooked insides, while still getting a crispy crust.
arrange each batch along the "spine" so that it is evenly spaced between the two elements on the top (strictly speaking, not necessary, but it compensates for any faulty fan action and allows the top to crisp more evenly)