Baby Carrier/Sling

I was wondering if anyone can tell me which carrier they prefered. I live in the city and dont drive. I use public transportation often. I dont wanna buy one and have her hate it. I see the range from front, to front and back, to hip carriers. She loves being on my shoulder, shame they dont make one placed there. Do they?lol
Thanks

I loved my infantino sling, they did a recall on the ones sold in the last 15-18 months or so, but are releasing the updated versions, luckily for me the one I bought for my son in 05 wasn't recalled, so I can still use it, but I would definately go for a sling if I wanted to make carrying the baby easy   my son did nothing but sleep everytime he was in his!

i have an infantino eurorider - kinda like a cheaper baby bjorn. zoe falls asleep in it all the time. it's been a life saver for running errands, and she's nice and snuggled up to my chest when she's in it. when she gets better head control, i can turn her around to face outwards, and the weight limit is 26 pounds.

I have a Hotsling and just got a Kelty Kids Backpack Carrier 1.0. My 11 month old son loves the backpack because he is up high and can see everything like being on shoulders. I like it because I have free hands with full range of movement and it does not weigh very much in backpack mode. It also has a little backpack that zips off the back for a kid or diaper bag or whatever. I used the Hotsling a lot when he was younger and still use it when we are out somewhere and he needs to take a nap. Hope that helps.