I used FSI ILG for over 20 years. Astra, CL 604 and GLEX. (Now train at CAE DFW). Always flew SFO-PHL. 30 min drive south on I-95 gets you to FSI.
You will want a car. Otherwise you're stuck at the nearby crappy hotel with nearby crappy restaurants.
I never could find a "good" hotel anywhere near the school. D'town ILG has a few hotels but the town shuts down after dark when all the bankers go home. Closer Christiana has a Hilton and Courtyard. Both pretty bad with little to choose from except chain restaurants. Avoid "Cheeseburger in Paradise" at all costs.
Best place I discovered is the Newark (DE) Courtyard on the UD campus. Nice facility in a college town with good food options. Downside? 20 mins to FSI. For me the drive was worth it. I got tired of the less-than-mediocre options near the school.
ILG FSI "Client Appreciation" lunch every Wednesday. Enjoy.