Kate, if you husband has the new ENfit connector system, that is the problem with formula clogging. The whole ENfit thing is just a nightmare (IMO). If this is the case, you can still get the old style connectors for the button type pegs. If he has the long tube, and its not a balloon, you can pull off the port adapter, (or cut it off) and either just push the end of syringe into the long tube end, or buy a classic port and put it onto the tubing end. I don't think you can mess with it if its a balloon type peg though. There is a guy I know via the Oley forum who does all kinds of adapting. There is a link on my blog to him under the Make Things Easier section (His name is Sanford) or you can message me and I'll look up his information. I don't really want to post his email publicly here). He knows a lot about long tubes. He's a cancer survivor though, not a PALS or CALS.
I agree with Affected I have the blend tec, and use it every single day. I don't know how it truly compares with a vitamix, people get their loyalties, if you know what I mean. Some swear by the Vitamix. But, you do need the power of one of these, whatever brand you choose, to truly convert table food to blended meals.
Warming liquids help thin them, and when you're blending, keep blending until you don't see particles, or the particles you do see will fit through a strainer (not a tea strainer, one that has holes just smaller than the opening through the tube) Shaking midways through the meal helps.
Milk and dairy really foam though, you can wait it out, or try hand stirring it in last.
Here is a recipe that doesn't need a blender, so bubbles aren't an issue. It comes to about 13 ounces/384ml, and has 530 calories. I listed brands for some ingredients, because calories do vary in some foods.
Start with whole milk,(150 kcal) add a protein powder to it that dissolves easily. (I use Jay Robb Protein Isololate, but, it lumps a little with just stirring. I mix it at night, and it sets in the fridge until morning, and I add hot coffee to it, no lumps then) However, Reserveage Grass Fed Whey vanilla (120 kcal) stirs in like a dream. Add a tablespoon of Nature's Way coconut oil warmed enough to be in liquid form, (130 kcal) and 1/2 cup Farmer's Market Organic Sweet Potato Puree (130 kcal). The sweet potato will settle if it sets too long, but shaking will bring it back together. Applesauce stirs in nicely too, but has only about a third the calories.