Personally, I would program the Baofeng to 1W instead of 5W. I'm not familiar with the Baofeng's interface specifically, but you should be able to switch it into high power pretty easily if you're having a hard time hitting your repeater or talking to someone on simplex with only 1W of power. Handheld radios have very sensitive "finals," which are the circuits that control the transmission and they're worn out quickly if you talk on the radio a lot with the highest power settings (think of running your car at high RPMs all the time and what it does to your engine). Although, at a price of only $30, I suppose it's no big deal to have to replace the radio if/when the finals do burn out. Even still, with your mobile Yaesu installed, you're likely to only use the handheld when you're walking around camp or spotting someone or going for a short hike or something, and you shouldn't 5W of power to talk with the rest of your group over that short of a distance.
As for the mobile radio - again, lower power (5W) tends to be better for the simplex frequencies, because we're usually in close range with one another. If you're programming repeaters that you know you'll be far away from, it doesn't hurt to set them up for one of the medium power settings. As stated, you can very quickly change the power setting on a Yaesu (it's one button on my FT-7800), but it'll revert back to whatever you have programmed into the memory as soon as you switch the channel and come back to your saved one.
