Hi

Definitely you should choose IIEST Shibpur CSE over NIT Silchar CSE. Following things to be considered -

1. IIEST Shibpur has been ranked 19th by MHRD. While NIT Silchar has a rank of 65.

2. IIEST Shibpur is in Howrah. It's proximity to the city of Kolkata gives you a lot exposure and tremendous opportunities to flourish.

3. Faculty is good at IIEST Shibpur.

4.At IIEST Shibpur, 

    Highest Package - 39.12 Lakhs

    Average Package - around 6 lakhs

  And in NIT Silchar,   

    Highest Package - 9 lakhs

    Average Package - 4 lakhs.

In short, placement wise also IIEST Shibpur stands better than CSE at NIT Silchar.

Best of Luck.

Hope this helps.

Cheers!