There are three very popular pumps if you are looking at pumping more than the once in a while with a hand-pump. The Isis by Avent is considered to be one of the easiest handpumps to use. I had one but rarely ever got more than about 4 oz between both sides with it. After I accidently killed my Isis... long story but don't forget to turn off the stockpot when you are sterilizing it and leave the house...
, thankfully I didn't burn the house down. Just killed the Isis, about half a dozen Avent bottles/nipples and a Calphalon stockpot.
I was never very prolific with hand-expressing either. I think I got a whooping ounce of BM if I was lucky, just couldn't get a good letdown with hand use. Okay that sounds a bit... racy.
Medela Pump in Style, Ameda Purely Yours, and Whisper Wear by Whisper Wear. The Whisper Wear came out after I bought my Purely Yours or I'd have gotten it.
Medela PIS is suppose to be a great dual pump. I didn't like it because it didn't have the closed/sealed pumping i.e. milk "could" back up into the pump system and there isn't anyway to sterilize it. It was very important to me to be able to use the pump for multiple babies if I was making the investment.
Ameda PY. The one I have. I bought it because it
1. has a close vaccum system so milk can't back into the pump and
2. it was quieter than the PIS
3. it had a larger versatility with 3 possible power sources (AC adapter, cigerette lighter OR it will take AA batteries!)
4. the comfort petal inserts to help with letdown (Medela didn't have those then)
5. the greater flexibility in "suction" settings which could simulate the nursing baby better which will increase your letdown and pumping volume.
6 it was also completely independant of the carrying bag so I didn't have to have this HUGE bag sitting on my desk, I still have a small spot on the corner of my computer desk where my little pump sits.
I've had my PY for almost 5 years and have used it with 3 babies... admittedly not as much with the last two as I did with DD because I wasn't a SAHM then BUT it still works perfect. I could routinely get 6-8 oz every time I pumped without having to dedicate the same amount of time or work as I would get I my previous 4 oz with the Isis. I plan on using it a lot more this time around because I'm also going to pump BM for the local Mother's Milk Bank here in Austin. Its such a worthy cause and I really want to help out with it, just need to be able to donate a minimum of 100 oz of BM.
Everyone I know that has a PIS, they last through *maybe* two babies. They purposely make them so that they don't last so that you have to buy another one.
I've only heard good things about the Whisper Wear and the price is pretty darn good too.
You might look into getting a hospital grade pump really only if you are looking at issues like preemies that can't latch onto the breast, nursing multiples, or more extreme nursing issues. You probably won't need to worry about that until after the baby is here.
Check to see if your insurance will cover the cost of the breast pump, many do. Especially if you've got a very savvy Peditirican that will write a "prescription" for breastmilk and a pump.
A lot of people say you don't "really" need a breastpump but for me I find it extremely useful. Being able to pump milk that will be in the freezer for my baby in case I'm not able to be there is very reassurring. My DH did create a very strong bonding with my DD through feeding her bottles of EBM, he often says he wishes he'd tried to bottle feed both boys a little bit more because he really did miss that one-on-one quiet time that feedings can give. He did make up for it in other ways but he really did enjoy those feedings. I have quite a few pictures of the two of them cuddled up passed out together after feedings.