My first couple of months after starting my transition, my legs (and sometimes arms and other areas) were basically razor burn city. I tried literally every razor and shaving cream under the sun to avail. Finally, i switched to an electric razor. No more razor burn. The shave's not as close, but i also don't look like a renaissance-era smallpox victim, so worth it.
It probably takes me 5 minutes to do everything (face, legs, arms, chest/abdomen) if I do it every day. It takes maybe 15 if I let it go more than 3 days or so.