Making the transition into clipless for the first time. How should road shoes fit? Should I size up 1/2 or a full size like I do for my running shoes?

I have wide feet and can wear a regular US size 9 in casual shoes, but my for my running shoes I always get a size 10, 2E width, which gives me about a thumb of space between my toes and the tip of the shoe . If I don't do this my toenails get bruised and I get terrible blisters on the sides of my big toe.

Do I need the extra toe room (lengthwise) in road shoes? Or should I just go with a size 9 wide and not have so much toe room?

thanks in advance!