luzarun,
I have a couple of friends who have gone thru CP in Delhi. After I-140 approval, it takes 4-6 months at the most to get the interview date for CP in Delhi. Once you get thru the interview, it takes 1-3 weeks to get your Plastic GC card in your hand after landing in US. About AOS, it is obvious that your case will go to BCIS, Texas and it may take 2-3 years (as per current processing status/time) to get thru I-485 step. So CP is much faster than AOS. CP has one disadvantage and a little risk. You will not get EAD and you should have to maintain your job/salary till final day of interview. Choose CP only if you are sure and confident about your job.