Lend lease's ability to allow the soviet player to not tech at all creates a huge exploit.
Problem: While the axis player has to spend mp and fuel on tech, the soviet player can abuse lend lease to spam conscripts, leaving him with a numerical superiority in the early game which can snowball. Furthermore, the soviet player can also access some critical units tech (and hence cost) free:
i.e. hmgs, Halftrack and M4C Shermans.
This allows the soviet player to overcome the axis player in a relatively low risk manner. (I am not claiming to be the best player but i think the end of match stats bear me out)
I submit the replay and screenshot as evidence.
This is the second time I've faced this today, its a bit frustrating.
Solution: Please bring Lend lease in line with all other commanders by restricting M4C shermans to tech buildings.