Originally Posted by pesty

Personally, I always found that my old SPD MTB pedals were always just easier to unclip from than any road pedal I've ever owned with the exception of Speedplay light action or low end Looks. I don't know if Shimano uses stiffer springs in the higher level pedals, but I do know that my old 105 SPD-SLs were fairly stiff, especially with new cleats, so trading in the Ultegra's for 105's might not do anything for you.

1nterceptor had a good idea with trying to find some used cleats, but keep in mind that the SPD-SL cleats have rubber grips on them to aid in traction when walking, and they become VERY slick when those come off.