I've been talking back and forth with a current grad student at Northwestern, and I asked her about about the research/phD rumor and this is what she said-
"I wouldn't say it's research based at all like no one I know at NU is working in a research lab at all and they we have a really big and popular clinic so I wouldn't think of it that way"
and she also said..
"But don't get me wrong there is a bunch of big deal research going on but I feel like coming from (her undergrad) that northwestern is a lot more clinic based than (her undergrad) was. There are a few PhDs but all the 2 year girls are there to go into clinical slp"
She had other really great things to say about the program as well and said that although it is hard, she thinks it is worth it.