I don't think it's even fair to compare these two. LIJ may fly under the radar, but it's a top notch program. SIUH is a good community program but certainly not up to par with LIJ in terms of volume, exposure, PD, faculty, or even location for that matter. There is hardly any overlap. From what I remember SIUH will have you travel to LIJ for C&A and I think you can land some elective time but other than that, they are very separate and distinct programs.
That said, SIUH may end up being a better fit for some especially those looking for a smaller program. It will also be considerably less competitive since LIJ appears to no longer be the well-kept secret it's been over the year. I would go see both yourself and get a feel for the programs. That feel factor holds the most weight IMO.
Btw is this in reference to next year's match or this?