Can you change the insulin delivery speed with the T-Slim or is it a one speed fits all?
There is one speed, and it's slow. The pump currently has a 0.3u plunger that must move back and forth, so you only get that 0.3u each second or so. All other pumps I know of use one long plunger for the cartridge, so they have the ability to dispense insulin continuously. I prefer slow bolusing, since it gives slightly more time to diffuse instead of pooling up several units at once.
That's what I thought, but wasn't completely sure. I agree on the slow delivery. One of the reasons that I am going to try the pump delivery method is because while Lantus works great for me it can really sting even at a slow delivery with the pen.
Relative to the slow absorption and super slow action rates, I have a hard time imagining speed of injection matters much one way or another.
I don't disagree with the first half of your comment, but try injecting very large volumes of insulin several times a day. If you are not a T2 with a very high insulin to carb ratio that sometimes require 25 or more bolus units per meal you have no ideal of the delivery discomfort that can happen with a large infusion of insulin. I can inject 10 or less units all day long with no problem, but trust me that a large volume injection with a pump or otherwise is not a pleasure if done a high rate of speed. That was the only reason I was concerned about variable speed ability of the pump. Now with all that said let me say if you are a T2 and you can handle the large volume injections of insulin a high speed more power to you.
If you use a lot of insulin, you may be interested to know that Tandem announced the "Flex" pump, which would hold 480u. Although I heard that the plunger was going to be larger for quicker dosing, though I bet that would still be slow compared to most pumps.