In reply to geoff.comley:
I just came back from Ama Dablam. Yes it's doable in 16 days. We made a return trip from Lukla in 11 days, with a day or two to spare at the end. However I'll recommend you to allow for more time, as the flight to Lukla is prone to delay by bad weather. We had to climb without a acclimatisation rest because of flight delays. Basically the planes can't take off/land when it's cloudy. The runway is amongst mountains and under 500m long! You can hire private choppers but they are very expensive.
On our way in our flight was canceled. After three days waiting in Kathmandu we decided to travel overland and walk to Lukla from Jiri. It took us three and a half days (recommended 8 days on guidebooks), plus another two days from Lukla to basecamp. The climb took us 4/5 days (1. base camp to camp 1, 2. optional rest day, 3. camp 1 to camp 2, 4. camp 2 to summit to camp 2, 5. camp 2 to base camp). There's two rest days at base camp/way out and 1.5 days to walk out. We would have put in more rest days at base camp if we had not booked our return flights. The food was incredible!
If you're planning to do the normal route (sw ridge), the whole route is covered with fixed ropes (in varying standards/conditions) and it seems to be what every one use. I've not seen any climbers carrying their own ropes. Apparently sherpas of the first team of each autumn will repair the existing fixed ropes. The old ones tend to be left laying around which can be messy and confusing. We hire a local company who deal with our permits, provide base camp catering and 4 sherpas to climb with us. The mountain tents are also set up by them as there is no room for more tents in some camps. They just leave their tents there for the whole season. This allowed us to climb with a relatively small rucksack (15-20kg) and climb in one push. For more detail you can read our blog here:
http://amadablamclimb.wordpress.com/