I am biased. My D graduated from Purdue with a degree in Chemical Engineering and is well employed. It’s been my opinion and observation that determined students make their way wherever they attend because they are focused and take advantage of opportunities afforded them. They are all ABET accredited so it’s up to him.
That said, I think Purdue has some definite advantages given the relatively small price differential. First, Purdue is very engineering centric. The engineering school is the center of campus. At many schools the engineering schools are set aside. As a university with a focus on engineering the Professional Practices office is very well set up to assist Engineering students in searching for coops, and looking for jobs. They have two very large engineering specific career fairs each year. There is a lot of opportunities for academic support because the school is large. I’m not saying Purdue will hand hold people. If the opportunities are not sought out they will be missed but they are there. I’m sure other universities have support as well but support for engineering at Purdue is very apparent.
Since your son is interested in cooping any cost differential can easily be made up through a coop. My D did a 5 term coop and was able to more than cover her OOS differential. Good luck to your son in his decision.