B.Tech

From previous 9+ years, I am working as a Mechanical Engineer in Pvt., PSU & Central Government. I feel that Lectureship job is best among PSU, RRB or other job except Class I Officer by IES (Indian Engineering Services), IFS (Indian Forest Services) or IAS (Indian Administrative services) by UPSC (Union Public Service Commission).But, it is also true apart from lectureship job, there are various good jobs.
Currently maximum PSU wants Gate qualified candidates. So GATE is must for Engineers.Prepare for GATE & Focus for Teaching Jobs in Engineering College. It gives you money, Respect & lot of freedom in life. Even if you can fight election during your job. During Job & after retirement, you will run a consultancy firm. There is no shift job in colleges. There are various types of Government holidays. OTHER OPTIONS ARE ALSO AVAILABLE, YOU CAN CHOOSE THEM SUCH AS i) For Power sector jobs join-Jobs for Mechanical & Electrical Engineers in Power Sectors through NPTIs course. ii) Name of Books for preparation of RRB & PSU exams - Name of books for RRB exam for SSE & JE & PSU companies for Engineers iii) Job profile of SSE in Railway - Job Profile Railway SSE (Senior Section Engineer) ,salary,RRB Group C post iv) Comparison between PSU Vs Central Govt. Jobs -PSU Vs Central Govt. such as NTPC vs Railways, (Public Sector Unit , Semi Government )
THERE IS ALSO A NEW OR UN COMMON WAY FOR GOOD JOBS. i) Take training of design software from any of Central Tool Rooms -AutoCad, Catia,Unigraphics , Pro E ,Solid works Courses by Central Tool Rooms under MSME in India (Part-I) and List of Common Design Courses at Tool room of India (under MSME) (Part-II)
SOLAR SECTOR MAY BE GOOD FOR YOU-Huge opportunities of Jobs in Solar Energy sector for Engineers,Accountants & Science graduate & also Training programme in Solar sector
AVIATION SECTOR IS ALSO NEW FOR GROWTH.SEE this lINK-AVIATION Sector COURSE-Aircraft Maintenance Engineering, Aeronautical Engineering in India

It depends on your area of interest. If you are interested in business or management orientation go with MBA. But, if you want to pursue or master a particular specialization, which you tend to do, go for M.Tech. Just make a clear decision about it as both are beneficial in terms if job aspects. You have other options like:
Construction management (it have many sub divisions - check NICMAR)
Structural engineering
Concrete technology
Ocean engineering
Irrigation engineering
Environmental engineering
Transportation
Remote sensing
Soil and foundation
Steel structures
Precast technology
Sustainability
If you have plan to start your own firm then go with construction management instead of doing MBA. You can also try structural, steel, precast engineering from some reputed institution. There is a lot of opportunities in foreign. Sustainability will be in high demand in near future.