101 sweep points only. No way to change this currently, so on a wideband sweep, you can easily miss narrowband features. There is now some beta software that specifically addresses this.No output power sweep. Useful for characterising non-linear devices.Slow sweep speed. About 10ms per point. The basic Copper Mountain VNA is about 100x faster. Believe me fast sweeps are a really helpful.Time Domain Reflectometry. You can do this in post-processing . Lots of professional high-end VNAs do not have this feature charge extra for this feature. Not sure why, it’s only a trivial IFFT. There is now some beta software that specifically addresses this.No de-embedding. 99.9% of people will never need this.Limited PC software.Limited frequency range. A lot of people will miss it not covering 915MHz and even more will miss 2.4GHz.The cal kit and cables that come with the kit are pretty cheap and nasty. That said, most pro VNAs don’t include cables or cal kits at all. These generally cost extra, and aren’t cheap.Calibration assumes ‘ideal’ calibration standards. Professional kits come with correction coefficients that allow more accurate calibration. Probably not a problem for most people working below 900MHz.