I've had a PPL/IMC for many years but am now doing an ME/IR at the bright young age of 53! Is it difficult with so much silver matter up top? Yes, but one of the amazing things about the flying business is that you are continually surprising yourself by what you can achieve if your motivation is strong enough.
So, a message to all you 30-something and 40- something youngsters: Go for it! Nothing is worse than having regrets at having missed an oppurtunity. Of course, I wish I had done all this 20 or more years ago.
Good luck to all of you, and beware of the doubters who will try and pull your wings off.