yup, roadie pedal and shoes displaces the power from your stroke in a larger area, so numbness and heating are less likely to happen. But another thing about numbness might be related to how tight your shoes are and about how much time of pedaling does it happen at.
Shin/knee gaurds, I use these
Picked them up last yr when they were ALOT cheaper, I think I paid 25 for the knees and 15 for the same style in elbows. I've crashed and rolled at 30+mph down Big bear w/o one single scratch. Good stuff and worth the money. Great to have around just in case some days you hit the trail and feel a lil outa it, you can strap them on just in case. Dress for the crash and not the ride. Next time I ride with you, I can bring them so you can try them out before you buy and you can get an idea on the sizes. If you ever come down to ride the Sycamore canyon here in SD, Beyond Bikes is about 15 minutes from the starting point or just off the freeway on your way home.