Is is safe to go for new iims?

I'm assuming you are taking about baby IIM's which are Sambalpur, Vizag, Amritsar,etc. Well it depends, if you are looking to learn from a good faculty and you want to do an MBA to have an IIM tag and your work experience is going beyond 36-48 months I would suggest you to take it up but in case you want a good ROI and great opportunities (with respect to profiles offered or a great start) I would say you should prefer other B-schools over since it is too soon to decide how well they will perform on their own.

The new IIMs, though not all, have started establishing themselves as institutes that are inline with aspirations of MBA students.
To specify, Ranchi, Rohtak, Raipur, Kashipur and Udaipur have gained some good news. There are functioning clubs, student bodies, placement activities and participation in national events from these schools. Evaluate these schools on following parameters:
Recognition: Good for 4-5 aforementioned new IIMs
Placements: Avg salaries have started hitting the 14lpa mark and median salaries a 16lpa mark.
Exchange: Raipur and Trichy give this opportunity for international exchange. Others also are entering the space.
Though not exhaustive, the above 3 categories can give a better picture of the situation.
So, summarizing, focus on the prep right now and by the time the results are out, you will have a better understanding of where your interests lie.

Yes it is safe only when you have a pressure to go for studies this year itself or there is no other good bschool in your hand.

So it depends which 2 bschools are you comparing. Not all private schools are good and not new IIM's are poor in conduction.

So based on your score, academics and other profile of yours you can check your chances through  CAT pathfinder tool.

Link: CAT Pathfinder Tool

Also later if you have any confusion between 2, let me know I shall guide you here.

Good luck!