Colleges in Allahabad

see both are very good and reputed colleges. as u want to do mechanical then it doesn't matter whare it is from as both are highly reputed college. so I think whatever u ll get just grab it.
best of luck

As a student of IIIT Allahabad I am aware of the fact that IIIT A has great placement statistics and is a name to reckon with. I have no direct comparison of the placement statistics of the two. I can surely say this that IIIT A is a great institute and should surely be kept as one of the options.

IT in IIIT Allahabad students recently get high salary packages in 2015

Yes IIITA is a very well known name in the field of IT and surely worth a try.Since there is no CSE branch here, the IT branch course structure and reputation is almost equivalent to the CSE only for any other college.

Rank around few thousands.

I fear you won't get IIITs.

Yes u have chance to get it.

The course for IT and CSE is not very different usually in any college and since IIITA is one of the premier institutes in India, its IT course is considered at par with the CSE course of good colleges with equally good placements and opportunities.