Never tried the speedplays but I had a similar problem with my Time Atac's. I've been riding on the Time's now for about 10 years on my MTB.. I love them there, nice and worn in giving me plenty of movement for the slow rock gardens and tricky technical climbs. I didn't have the funds for a new set of pedals when I bought a road bike however, so I moved the Time's over. With all of that movement however I felt totally out of sync from what I was trying to do. I too ended up with a set of 6700's and the larger platform and less float has made all of the difference. Very happy with the purchase.