Hello,
In my opinion both the colleges are equally good and they do stand important nationally. Although they do not have their own campuses and they are operating from NITs in the respective states. Placements salary are more or less the same for both but people are choosing IIIT Sonepat over IIIT Kota because it is closer to city and hiring people there thus becomes easier. Although due to increasing placements I would also suggest you IIT Sonepat.
You said that you are really interested then if you are not getting your desired branch I would say yes you could try again next year. It depends on your hard work.
For checking more colleges you could use this link- https://engineering.careers360.com/jee-main-college-predictor?icn=jee-main-cp-lp&ici=nav-header_engg
Hope it helps,
Good luck.
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