For what it's worth, I live in Sansom now. It's not the nicest place and you can def. find a nicer place for the same price (and likely even for less). That being said, it was super nice first semester being able to roll out of bed and be in class in 3-5 minutes. I just didn't want to have to deal with housing as a 1L. I didn't really know anything about Philly or where would be good or what a decent rental amount would be. So I just took a place in Sansom (I live in one of the 2 bedroom apt's). It's clearly not a luxury living type place, but it's also not a hell-hole. It served its purpose this year for me, and I'll be living in center city next year now that I know what areas I like.
If you have the time and are willing to look for housing, you have a million options open to you. If you want to live in west philly but not in Sansom, look around 40th and spruce/locust. Past 40th on market starts getting sketchy, but if you go south to spruce/locust it's nice and safe for a ways (lots of profs live in row houses by there).There are a bunch of stores by there, the gym is 3 blocks away and the school just a couple more after that.
For those that are stil considering Sansom, I have some pics of my apartment I took last semester to show my parents. If you want me to send them to you, email me at firstname.lastname@example.org
and I'd be happy to forward them on to you.