KIT College of Engineering, Kolhapur

First of all, as both of these colleges are affiliated to Pune University so they are almost the same with respect to their conduct and courseware. There is no significant difference between the faculty and facilities as well. Being a second year mechanical student at Sinhgad, the only difference I felt was being in the city of Pune. As compared to Nashik, Pune is quite developed in all the aspects and evolved as a student hub. The advantage of coming to Pune is that you can interact with students from various colleges having common interests from the likes of COEP and IISER too. There are core industries in the city also which can provide you a lot of exposure in this field. Moreover, you will find better coaching options for the preparation of higher education/jobs in this city. I've been a student in Nashik until my class 12th but have experienced a massive change in everything since I've come to Pune. So, going along with the things I've said Sinhgad seems a fair bet. However, I don't intend to undermine K. K. Wagh CoE which is undoubtedly the best one in Nashik and at par with Sinhgad CoE, Vadgaon. Ultimately, what matters is how you carry yourself in those four years. Being in Pune will just make your ride a bit easier but the consistent effort is always required from your side.
Good luck.
Feel free to ask any other doubt in case you have any.