If you can get your hands on the pedals before buying, you could easily measure the distance from the face of the crank to the center of the cleat. You should notice a difference of about a quarter of an inch on the two pedals that you have.

I am pretty sure that you can rule out Speedplays, who advertise the lowest Q Factor available.

I use Time ATACs, and I have plenty of clearance even with my Winter boots (Lake MXZ303s in the wide version).