I am not a Tslim user but you might be able to use a temp basal (which can be dialed down as far as 0%) every day to make this work. You might set a temp basal at say 83% every 24 hours (83% of 2.4 gives you a total daily basal of 2). Temp basals can be set for 72 hours but setting it every 24hrs at the same time of day might be easier to remember. (This example assumes your daughter's daily basal requirement turns out to be the same as on MDI.)
The odds are that her insulin needs will soon go up enough to make the Tandem work. IMO though I think that you should wait to buy the t-slim until it is the right pump for her. If you're going to start using the un-tethered approach right off the bat, then it seems to me kind of crazy to get this pump when you won't be using half the benefits of getting a pump. I think it's dangerous to start playing the game of temporary basals every day because what happens when you forget?
Obviously right now the Animas or Medtronic pumps are a better choice for your daughter. However since the t-slim is the coolest kid on the block and it's what your daughter wants, you're probably better off delaying the pump purchase rather than buying another one that she'll have to use for 4 years.
I have MM pump, and for each 1/2 hour increment on basal, I can choose to set it to 0.0 as the basal rate.
Does the t-Slim allow 0.0 ? I assume .1 is the minimum 'increment', eg .1, .2 , etc. but might not be the minimal value.
So why not just have .1 set for 20 of the hours, and 0.0 set for the other 4 hours ?
If you space out the 0.0, especially if t-Slim can do 1/2 hour increments, it should be ok.
That is quite good: 15 minutes slot.
Go and set 0 every other slot to get 0,05 /hour units, for example.
The only problem I could see is, for any pump, the risk of occlusions with so a low flow rate.
But tandem has an its own system which garantees more precision that every other pump on market, and it's valuable when you have such high insulin sensitivity.
You have to try and see.
For this reason, I would recommend the MM revel or the ping. I realize the t:slim looks cool, and that's something in and of itself. BUT, if I were picking a pump for a kid, I would want to make sure it has the ability to set really low basal rates (both the ping and the revel can go as low as 0.025 u/H for basal, and the Ping even continues to allow these small increments after the 1.0 u/H mark is passed).
In addition (and this is just my opinion as a T1, so take it for what it's worth), if I were picking a pump for a young child, I would stick with something that has a proven track record in the pediatric population. MMs have a proven track record in both adult and pediatric populations, and the Ping has been out for quite some time.
Pumping is great, but it requires a lot of work and you always have to be on the lookout for DKA. Any pump can fail, but sticking with a device that has been on the market for many years will reduce that risk. Kids can go into DKA VERY quickly, and for that reason I would recommend sticking to a pump that has a proven track record. But again, just my opinion. In the end, you know your daughter best and what is going to motivate her. If the "cool" factor of the t:slim outweighs the risks (and it very well might), go for it.
I agree with MBP completely. Chances are that you will need a few different basal rates throughout the day. If the Tslim can only go down to 0.1 U/H, then I think you need to consider another pump. One that will let you fine tune your basals and boluses more accurately.