I don't know anything about Yonkers but I agree with most of what
@em_2017 said about Rush. I will say don't be alarmed by a seemingly quiet ED; that may just mean the department and hospital are well-run. One of the programs I interviewed at in Detroit did about 130,000 visits a year but made an effort to not have people stacking up in hallway beds and the waiting room. The volume was close to double Rush's, but it was even quieter because the department and hospital were just very efficient. Go to Cook County and you get that inner city zoo feel, but it isn't because the volume is that much higher. It's because the hospital is under-resourced and inefficient. Everyone has to make their own call on what that means in terms of training...I personally don't want to spend that much of my time wheeling my own patients to radiology and doing my own phlebotomy...I learned how to do this well enough on my M3 rotations at County.
The volume at Rush is about 75,000 per year (and increasing every year). It is a level 2, Cook County is directly across the street, and the city of Chicago is full of hospitals, including several level 1's. This has implications for what you'll see in your ED months at Rush. Now I think the trauma experience in the curriculum is going to be just fine, because it is at county. But you spend 7-8 months each year in Rush's ED, and you won't see hardly any trauma during those months. Keep in mind, this is also how the curriculum is set up in the legendary Cook County residency program. You see trauma when you're on trauma service, not on your ED months.
If you train in a level 1 in a small or midsize city (Detroit, Memphis, Akron, Penn State in Hershey, etc), you'll see similar ED volumes, but the 75,000-100,000 visits will typically include a lot more trauma than what Rush sees. The trade off is you'll miss out on some of the crazy tertiary care/academic stuff you'll see at Rush. Does it matter? Hard to say. Couple of things worth considering though.
When you work in an ED that sees crazy medically complex patients, you work with attendings that like that stuff and are equipped to handle it. The other thing is what you'll see on your off-service rotations. The stuff in Rush's ICUs and PICU is some of the bread and butter, but a lot of crazier stuff that simply gets transferred out of other centers because they weren't equipped to deal with it. And when you work with the specialists that are equipped, you see and do crazy ****.
For example, as an M4 at Rush on a PICU selective, I assisted one of our Peds CV surgeons while she cracked the chest on a coding 12 week infant, in the kid's PICU room, to do an open heart ECMO cannulation. If you were an EM resident on your PICU month, you would have been front and center for that resuscitation. And if you wanted to, you could manage that kid's care day to day. You're just not going to see that kind of thing everywhere, and I've got dozens of stories like this.
Again does it matter? Hard to say. You go to a community program and you'll certainly learn how to, say, workup kids with fever. You come to Rush and you'll learn how to do it in normal kids, but also kids who have an open chest in the PICU, or had a bone marrow transplant two days ago, or who are getting desensitized to Rituximab, which they need because they developed a B-cell lymphoma after their kidney transplant (which they needed because of their extremely rare genetic disorder that gave them FSGS). It's like swinging a leaded bat. If you can work up and dispo fever in those kids, the otherwise healthy 7 month old with bronchiolitis becomes something you can handle 6 beers deep. If you're not interested in training with those kinds of more challenging patients, Rush isn't the place for you.
Another thing I can say about Rush's program is that the hospital has a lot of resources and consequently, the ED already has a lot of the small perks other places either brag about, or say they are working on getting. Qpath for logging ultrasound scans? Check. 24/7 social work/case management? Check. 24/7 ED pharmacist? Check. And if there's something they don't have that you want, if you can make a strong enough case for it, they've got the dough to procure it.
Last consideration, which if you're lazy, or have a family, or both, is a big consideration, is that their curriculum has the fewest shifts of any place I interviewed/rotated. The shifts are also 9's with the last hour protected, and you sign out your patients so you don't have to wait around for any lingering results or social issues that are holding up your dispo. Places that have 9's or 10's but don't allow sign out of patients are deluding you, because those shifts regularly turn into 12's or worse.