If you have had 2-3 years of broad (working on projects across sectors, functions, geographies) exposure stint at Mck/BCG/Bain, then there are not many hard/tangible advantages of MBA. Especially if you are considering to continue in consulting post MBA.
- Knowledge/Frameworks/Approaches - Consulting is called 'extended MBA' for a reason. If you have worked on enough variety of projects in big firms, there is limited value add on this front.
- Career Progression within consulting - Don't see MBA adding too much value add. Will it accelerate the way forward? Don't think so. Will it help you change sector focus/office - probably, but if you are selected for MBA sponsorship, means you are a stellar performer, in any case you can apply for global rotation programs etc. MBA degree influence is minimal.
- Monetory considerations - Spending during MBA and opportuity cost of not working for 2 years means, its a significant monetory investment
HOWEVER soft benifits galore! Opportunity to network with diverse group of people, people coming from other regions, other walks of life definitely add a few perspectives to your thinking. And of course, the break from 2-3-4 years of grueling analyst lifestyle is a welcome one. It's a nice time to recharge your batteries and get ready for the EM->Partner roles.
Ultimately, it all boils down to your long term career strategy. Spend some time evaluating your options, do talk to those from your office who have taken MBA sponsrships and who have not. A clearer picture should emerge.
All the best. Feel free to get in touch for further guidance.