Use both to your advantage. Currently, the value of Steem is rising, so perhaps purchasing Steem is the better idea.
Your account on Steem is a business. Steem Power is your invested share. It cannot be instantly withdrawn.
Steem is the liquid assets that you have. Like oil or gold, it fluctuates so when to buy/sell is important to note.
SBD is you guaranteed dollar value.
Thanks I did a lot of reading about it yesterday, currently looking to earn and hold, see what happens with this bull market. So that said I will slowly try to power up as I am not interested in cashing out soon.