I actually bought this kit so I could try using the Ascent Series blending bowls on it, even though they are listed as not compatible. Some reviewers stated they worked and some stated they did not. I can tell you, along with the provided pictures, you can make them work, but it's not an ideal setup. The design of this adapter seems odd, with what looks like a container being attached to the adapter, of which you actually install the blending cups into while it's upside-down. It took me a while to figure out why they did this. I believe it was for safety. If they did not have the outer container on the adapter then you could potentially install the adapter on the base and run it without a cup being installed!... or if the cup somehow came loose it could be very dangerous. That is my best guess as to why the outer container was added to the adapter base. In addition, the Ascent series cups and bowls have magnetic strips installed at the connection point to signal that a cup or bowl is installed to a digital type base, in this way they can prevent the base from running if there is no cup or bowl installed. Of course my old 5200 series does not have any sort of safety mechanism to prevent this. What is not ideal? 1. It is awkward to install the cups on the adapter with the outer container part there, but not too bad. If you use the Ascent bowls it is much more awkward because the bowls are so much shorter and down in the container, making them hard to install and remove, especially if you have large hands. 2. As others have stated, the shape of the cups narrows so large chunks of material can get jammed high up in the cup and not get blended. 3. Cleaning the adapter is difficult because the blade and dirty areas are in tight proximity to the outer container housing that is part of the adapter. You also cannot just dump soapy water in there and run the blender, because the adapters container housing has holes at the base to drain out, ie it does not hold liquid in itself, nor does it have a lid anyway. 4. I suspect some people will have issues with this setup leaking. It would not be hard to get food material between the rubber seal on the adapter and the cup/bowl mating surfaces, thus likely causing a leak. In fact, if you install a cup or bowl to blend and then remove it from the adapter and then place the adapter right side up again, it's almost certain food contaminate will drip onto that mating seal surface, so if a cup or bowl is reinstalled without first cleaning it's likely to leak. I also found I had to use a lot of force to tighten the cups/bowls so they would not leak. A lot of pressure is created inside the cup/bowls when blending, not to mention expansion due to the heat being generated inside the cups/bowls. I have very strong hands and arms and the force needed to install and remove the cups/bowls from the adapter such that they would not leak was quite tight and difficult to remove afterward. People without as much strength might find it difficult to get it tight enough to stop leaking... and/or then find it very hard to remove the cups/bowls from the adapter. 5. As with most Vitamix stuff, it's quite expensive! I got these things on good sales and it was $130 for the adapter and bowls. I could have bought a "Tribest Personal Blender PB-250", or similar, for half the price without a lot of the above mentioned issues. For myself, I like the high quality Vitamix build and materials, and not having multiple blenders for slightly different purposes, so it's still worth it for me, but that's a personal choice.