Is Vignan University, Guntur a good college for a B.Tech in bioinformatics or a B.Tech in biotech? How good are the placements and scope for higher studies abroad?

All the private universities in India, except maybe 2–3, are trying their level best to establish themselves and Vignan is no exception. If you are considering joining the university then you should know the following. 

• Fees are high so plan well before joining. For a 4-year long B.Tech, the total course fee is around 9 lakhs. 
• Second, the syllabus keeps getting updated each year. This makes covering the syllabus, a bit tricky. 
• The same faculty will set the question paper so I think getting through with good grades won't be an issue.

Finally, you should join biotech only if you wish to study MS abroad. Otherwise, don’t join the institute.