Midwife and doula
However, If you loved your doula, and can afford to have both, I would! You already know that your doula provides the kind of care and comfort you like.
Here's the analogy I give: I consider myself a lifeguard. The doula is your swim coach, right there in the water with you. In a perfect world, neither of us are needed. I can certainly coach as part of my work as a lifeguard, but when it comes down to it, my job is to keep mom and baby safe. In an emergency, when my skills are most needed, is when I'm the least able to be a coach. Also in an emergency, my assistant is my assistant and not your coach.
This is a really good question and one i pondered throughout my last pregnancy and the bottom line is YOU CANT GO WRONG HIRING A LABOR DOULA! I am a postpartum doula and i belong to a group of doulas - pp and labor - so i have so many friends and aquaintance's who are labor doulas - i felt a little 'on the spot' when it came to picking one to hire.
My last home birth (12 years ago) was about as smooth and easy as a birth could be - my midwife's assistant came early and acted as my doula - it really was a great birth and i was convinced this one would be the same way...not so!
This time, the labor was far more intense, my midwife was not great with comfort measures - her assistant was even worse. Although it was a short labor, i spent most of it thrashing around in my birth pool howling "no no no!" like a petulant 2 yr old. I could have REALLY USED a labor doula! You never know what kind of labor you are going to have ...and hiring a doula is a little like preparing for the worst. You might have quick easy birth and not really need her....but if not, you need the help only a doula can provide. My DH was very cost conscious this pregnancy too - but i feel the cost of a labor doula is WELL WORTH IT!