Getting a job has no relation with age. Its all knowledge, skills, presentation, personality that will land you a good job.
Now coming to the question of value of CA after MBA :
Think rationally, If you complete your CA at 40. Lets say, Worst case scenario.
You will get low paying job. Lets face it !
BUT After doing 20 years of Job
Now you are in good company, with good job, Next year you will retire.
NOW COMES THE VALUE OF CA : You can easily join any firm as a senior partner. No firm will ask you about No. of attempts, or at what age you Qualified CA. THEY WILL BE AFTER YOUR NETWORK, EXPERIENCE, INDUSTRY SPECIFIC SKILLS.
When you become a partner, you will start a new life. As you will grow old, you will be given only signatory work. Your value will increase manifold when you are way above than retirement age. Reality is that, you will get pension in Private sector, which will be in relation to Industrial remuneration of any senior CA.
NO OLD ENGINEER, OLD MBA, OLD CS, OLD CWA can match the lifestyle of an OLD CA.
So invest your time in CA, you will reap huge benefits when the time will come.