I carry my emergency reload in a mag pouch on opposite side for quick access. I don't consider that a spare, nor is it extra. It's very much a part of my every day carry system.
I carry my "spare/extra" mag. in my jacket pocket, or sometimes in back pocket, depending on what I'm wearing. I carry as above when using a higher capacity pistol, but usually without the spare/extra.
Yes, I know, some have it figured out that I'll never need a reload in a gunfight, let alone a speed load, and I guess there's no sense in arguing about the value of the better sense of security. And driving around on day to day business, I have extra magazines in the car for the unforseen that the odds makers on the board say will never happen.
And, oh yes, I carry an extra speedloader for my J-frame back-up. It's carried in my upper right vest or jacket pocket. The J-frame (or LCR), carried in an inside vest pocket) also allows me to secure my primary weapon in the car lock box and still be armed at the Dr.'s, etc. office, etc.
I've given up trying to figure if I'm getting more parnoid with age or just smarter. I just go with the "feeling".
Just my thoughts on the matter.