I did some testing in mine and posted results to reddit 10 days ago now but for those interested, my setup is below and I will be comparing temps and noice to my previous Dan A4.
GPU - Gigabyte 2080ti Windforce OC. Replaced fans with 3 x Noctua A9x14 Chromax fans and created a temporary cardboard duct from the fans to the side panel.
CPU - AMD Ryzen 7 3700x with Noctua l9a and reused the duct from my A4, raising it ~5mm to the side panel and sealing the gap between the fan and duct. Also included my previous Black ridge results in the Dan A4 with VLP RAM and Noctua A12x15 (swapped to l9a and faster RAM due to better performance than cooler CPU and slower RAM)
GPU Results - Set to 950mV in Afterburner.
Dan A4 - 41.2dBA (36.6dBA with side cover off), Freq - 1965MHz, Temp - 82C.
Sentry 2.0 - 38.4dBa, Freq - 1980MHz, Temp - 78C
CPU Results - Testing done in Cinebench R20 and temps with small FFTs in Prime 95
Dan A4 + BR - 80W PPT - 4741 points (100%)- 86C
Dan A4 + L9a - 75W PPT - 4677 points (98.6%) - 85C
Sentry 2.0 - 65W PPT - 4684 points (98.8%) - 87C
Conclusions
GPU runs cooler and quieter - Even with the louder Chromax fans compared to the normal A9x14s I had on previously, the GPU compartment is about 10mm more recessed than the compartment in the Dan A4. So this explains why the noise is slightly above the Dan A4 with the side cover off but much lower than with the panel on (turbulence).
CPU runs warmer. I try to get all temps in Prime 95 around the same mid 80s temps. I set the CPU power limit accordingly. The Black ridge was able to run at 80W, L9a in the Dan A4 at 75W and 65W in the Sentry 2.0. This makes sense as the hot air is able to dissipate above the cooler in the Dan A4, but is more limited in the Sentry 2.0. No difference in gaming, as the CPU never reaches 65W. Perhaps when games utilize all cores this will change. Cinebench score however almost matches the 10W higher 75W PPT due to my motherboard's offset voltage now working in the latest firmware, which I reduced voltage by 0.075V.