Hey there

If you are not looking just for nit tag then go for SVU Tirupati. Because if you compare both the colleges you will find that SVU Tirupati has much lower fees than nit Sikkim. Also nit Sikkim is an Eastern college and so cutoffs are low due to which it does not have that reputation than other nits. But it's up to you what you choose.

Check about SVU Tirupati

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.careers360.com/university/sri-venkateswara-university-tirupati/amp&ved=2ahUKEwjfhoj7-7DjAhWMrI8KHQpBDVwQFjAkegQIAhAB&usg=AOvVaw0Rxvkwt7riAURd9smiDIFE&ampcf=1&cshid=1562989337585

Good luck