Either unit will work fine in a $400 studio. My thought is the reviewer chose the Tascam DP-03 over the R8 to not invest money into an audio interface, USB, or controller there's no intent to ever connect to a PC and the fact the Tascam has robust audio editing where the R8 has practically none. Navigating and operation of the Tascam is less complicated and easier.

From the Video summary:
"Budget Friendly, mobile, internet safe, reliable, and easy to use, this home studio setup solution will outlast any PC software-based DAW platform on the market. Watch all of this video now to see how you can have a great enduring home studio setup without any of the hassles or risks of using a personal computer and or spending a lot of cash."

I believe either unit is up to the task but with the R8 shipping with DAW software, built-in audio interface and controller, Zoom is optimized to be used in conjunction with a PC. The DP-03 is optimized to be a stand alone home recorder.

BIAB Ultra Pak+ 2024:RB 2024, Latest builds: Dell Optiplex 7040 Desktop; Windows-10-64 bit, Intel Core i7-6700 3.4GHz CPU and 16 GB Ram Memory.