How good is PGDM- Full time at IMT Ghaziabad with almost 4 years work ex?

IMT Ghaziabad placement and admission process both lay great emphasis on Work Experience. So your work experience of 4 years will define work in your favor not only during the GE-PI rounds but during placements also.

One way to determine if your admission will be worth leaving your job is to calculate your ROI (Fees vs Avg CTC *2 with 2 yrs of loss in pay based on your existing CTC). 

If you are confident enough you target other better B Schools also for wider prospects. You can check the career prospects of the field you have been working in and in case you are switching careers do the same for that field too. Check the best offers in that line and compare it with other B Schools. Such in-depth research will help you make a better decision that you won’t regret later.