Savage Wilderness Safaris are also a very safe bet.
They have a fantastic camp site very close to the mountain with white water rafting at your doorstep. http://www.youtube.com/watch?v=lk_M3gzugjQ
From memory he "stole" his mpishi (chef) from the legendary Carnivore restaurant in Nairobi, so the food is wonderful - don't miss his tomato soup. You'll never eat Campbells again! All of this in an atmosphere of old world charm - its just so "civilised' that you are almost expecting Stanley to step out of the bushes with his famous greeting!
Once actually on the mountain, nothing is too much trouble. I can assure you, there is ABSOLUTELY NOTHING better during that last never-ending mile to the camp each day, than seeing the porters coming back to carry your rucksack! And this is after they have already carried sacks more than twice as heavy, AND set up camp, AND cooked a fantastic meal!
Their equipment is the latest and their knowledge and expertise gives you the confidence you need to give your best effort.
I seriously doubt there is anyone better than Mark, his wife and two sons, for a trip to Mt Kenya, or any of the other Safaris he organizes.
By the way, I have no connection with this company. I searched the net, and this is the url I found for them - http://www.whitewaterkenya.com/index.html