Congrats on the new baby coming! How exciting your life will certainly become again.
I have a an almost 3 year old and a 7 month old, and breastfed exclusively with both until returning to work around the 5 month mark. I don't think there are BPA issues with Medela's bottles, but I'm not sure. I have the Medela Pump in Style Advanced, and it allowed me to effectively and efficiently pump enough milk ahead of my return to work (had 19 plastic shoe boxes full of milk bags in the deep freeze before returning to to work) and while working again to keep my first (and now my second) fed with breast milk bottles at daycare.
I ABSOLUTELY LOVE my pump! I haven't used any other pumps, so I don't have any comparisons for you. However, I can say that in my experience (2-3 pumps/day in addition to nursing on demand full time), I never experienced discomfort or soreness with the pump, probably because it has an adjustable strength dial and let down button, so I can customize my pumping session to my needs and let down pattern. The let down feature really seemed real enough to me in the way that it had the frantic, quick style of sucking that a baby does in the beginning of nursing, then moves to the long draws after about a minute or two, like when your milk lets down naturally. If you let down faster, you can simply push the button and go to the long draw cycle. There aren't nipple cushions, but if you're positioned correctly, there isn't any friction or rubbing to cause discomfort. I know you can buy different sized shields to assist with fit if you need to, and other parts can be replaced for that matter too. I found it helpful to use Lansinoh lanolin after nearly every feeding and after every pumping session to keep the "ladies" in top form, if you know what I mean.
With my pump, I'm completely empty on both sides within 5-10 minutes, both bottles are full--and near the end of each session, while still pumping merrily away, I'm able to massage each side and gently squeeze down from the top to get all the milk out so I'm completely empty. I just have to be careful not to squeeze too close to where my breast enters the shield or the seal can break and I lose suction for a moment. When that happens, I just reposition and go back on my merry way.
One mom who responded indicated concerns with getting milk back up into the motor; with all the pumping I've done, I'd have to say your odds of that happening are very slim. You would have to tip the bottles nearly completely back on themselves to allow the milk to get back up near the tubing entrance for it to leave the bottle and go into the tubing. Once, after being way overdue to pump, I overflowed one bottle, but it didn't go into the tubing, it simply leaked out the top of the bottle from the place where the bottle screws onto the connection for the shield. So, having experienced that, I'd say that if you keep your bottles sitting upright (on your thighs) in the little stands that comes with the set, you should never have to worry about milk going back up the tubing and into the motor.
I was blessed to nurse for 13 1/2 months with my first son, and hope to go as long for my second. I believe that my Medela made it possible to go the distance after returning to work full time since it effectively allowed me to empty both breasts at least twice a day while away from my baby, basically mimicking the two feedings I was missing while working. I'd say, get the Medela, as I think you will most likely be completely satisfied and have a wonderful nursing and pumping experience with it.
Good luck and I hope you have a wonderful delivery and nursing/pumping experience with your new baby!