In discussing my cartridge options with the folks at VPI they emphatically endorsed the Dynavector over all other choices in my price range, indicating that the cartridge weight, compliance, etc. were perfectly suited to the Scout series. I went with a 20XH as a result and was very pleased with the performance. I then upgraded to the 20XM made specially for VPI and found it to be faster and slightly more detailed than the higher output version. This was not a huge difference but was "worth" the price difference, in my view. I haven't heard the Blackbird, though I'm sure it is quite good. Here I think the issue is that the Dyna simply mates better with the Scout series table than most other cartridges. I think when you are using a unipivot arm the design parameters of the cartridge become more critical. I'd go with the folks who build the table on this one and buy the Dyna.