how does the new model differ from the older model on sale for $274.95? is it purely cosmetic or is their a functional difference?
It is a completely new design of both the first and second stages. Mostly it is cosmetic, the first stage is still a balanced design offering excellent performance, but also a new cosmetic design.
Is this functionally identical to the regular Oasis without the Red cover?
Yes, its just a newer model with cosmetic differences.