The following answer to this question will enlist some facts to the students. Among the IIITs, as mentioned above, are completely new, so they still not have alumni networks. 

The course offered by these institutes is the best if you want to learn or do research in the future. But if placements are considered, IIIT Lucknow and IIIT Naya Raipur are still lagging far behind than NIT Raipur, a well-established institute among the two IIITs. 

NIT Raipur has an infinite alumni network. Companies like Oracle, Microsoft, Amazon make a regular visit to complete their recruitment process with CTCs of 8+ LPA, specifically for the CS and IT students.

The biggest cons of NIT Raipur is its Hostel, as only 30% of students here take hostel accommodation, and the rest 70% find PGs, rent houses, or flats for their accommodation.

Another disadvantage of this institute is the outdated syllabus of NIT Raipur, along with the grading techniques.

Therefore the choice is obvious. If a student is interested in carrying on higher studies, they can go for IIIT Naya Raipur. It is well-established and has a permanent campus. But, IIIT Lucknow is carrying out its administration as a temporary campus.

Besides, if you want placement immediately after completing your studies, you must choose NIT Raipur.