From personal experience, it is far, far too much work for anyone doing a demanding job. You are looking at an average of 12-15 hours a week, perhaps more, for 2.5 years.
Don't make the mistake of thinking the M in MBA means it is like any part-time Masters; it isn't. The volume of work is quite a bit higher.
Good luck to you if you have this amount of free time during the week, but otherwise you can write off your weekends for the foreseeable future and look forward to those games of catch up when you inevitably miss the odd couple of weekends and find yourself weeks behind.
It's do-able if you can do a 4 day week at work or finish at 1630 every day.
Have a think about whether or not you really need to do it, though. Consulting-wise, it would have been a waste of time for me in the short to medium term as I have now passed the MBA entry point. If you decide you do need to do it, then seriously consider just taking the financial hit and doing it full time.