Got mine on launch day also no regrets the differences for me were minor since i upgraded from an iPhone 8.
The reason to upgrade was for the dual sim ability as well as further future proofing against future iOS updates
The only annoyance I've found is that screen protectors don't work correctly like they have done on the iPhone 8 but aside from that been happy with the device.
There's more to future proofing the iPhone SE 2020 edition than just future ios updates and Dual Sim(esim). You also get Gigabit Class LTE,Wifi 6, A13 CHIP, Express Transit with Power Reserve, 3GB of Ram, all lacking in the iPhone 8.
The rear camera is different and improved on the SE 2020 edition vs iPhone 8.
The iPhone 8 and iPhone SE both have a single 12MP, camera with 1.8 aperture along with 5x digital zoom. The iPhone SE 2020 edition is now able to do Portrait Mode (limited to people), Portrait Lighting, Smart HDR, and QuickTake video, all of which are not available on the iPhone 8. Also the iPhone SE 2020 edition front camera can now take portrait videos with the front camera (couldn't do that on iPhone 8).
The SE has Apple’s A13 Bionic chip, while the iPhone 8 is powered by the A11 Bionic chip.
The iPhone 8 has 2GB of RAM. Now, the SE 2020 edition iPhone has 3GB of RAM.
Both the iPhone 8 and the iPhone SE 2020 edition are IP67 rated for water and dust resistance which allows them to go into water up to 1 and a half meters for up to 30 minutes. Both the iPhone 8 and the new iPhone SE 2020 edition can do wireless charging. They also both have the same stereo speakers, Apple Pay via NFC, and Bluetooth 5. The SE 2020 edition iPhone has the new Wifi 6 standard 802.11/a/b/g/n/ac/ax. Whereas, the iPhone 8 has the old wifi 5 standard 802.11/a/b/g/n/ac.
Info on wifi 6 and why its awesome
https://www.theverge.com/2019/2/21/18232026/wi-fi-6-speed-explained-router-wifi-how-does-work
Gigabit-class LTE:was first included/introduced on the iPhone XS and iPhone XS Max. Also included on 11,11 Pro, 11 Pro MAX, and now on the iPhone SE 2020 edition
The iPhone 8,iPhone 8 Plus, and iPhone X got the LTE Advanced modem which supports theoretical speeds up to 600Mbps
The iPhone 7 and iPhone 7 Plus got the LTE Advanced modem which supports theoretical speeds up to 450 Mbps
The iPhone 6s and 6s Plus, got LTE Advanced modem that supports theoretical speeds up to 300 Mbps
The iPhone 6/6 Plus got LTE-Advanced that supports theoretical speeds up to 150 Mbps
dual SIM (eSIM): was first included/introduced on the iPhone XS and iPhone XS Max. Also included on 11,11 Pro, 11 Pro MAX, and now included in the iPhone SE 2020 edition
The A13 chip, Wi‑Fi 6 802.11ax, are 2 new features first introduced/included on the iPhone 11,11 Pro, and 11 Pro MAX and now on the new iPhone SE 2020 edition.
FYI: iPhone X, iPhone 8 and previous generation iPhones do NOT get Express Card with Power Reserve.
Express Cards with Power Reserve feature which is included in the iPhone SE 2020 edition also included in the iPhone XS, 11 and 11 Pro, allows for authentication of Express Transit cards even when an iPhone's battery is exhausted. It can also be used for the "CarKey" function that Apple has in the works which will let an iPhone serve as an alternative to a traditional car key in vehicles that support the feature.
Lets not forget the iPhone SE 2020 edition supports more bands than the iPhone 8:
iPhone SE 2020 FDD-LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 18, 19, 20, 25, 26, 29, 30, 66, 71)
TD‑LTE (Bands 34, 38, 39, 40, 41, 42, 46, 48)
iPhone 8: FDD-LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 18, 19, 20, 25, 26, 29, 30, 66)
TD‑LTE(Bands 34, 38, 39, 40, 41)
Overall the iPhone SE 2020 is a great iPhone especially for the price.
Only the iPhone 11,11 Pro, 11 Pro Max, and now the New SE 2020 edition iPhone have wifi 6.
Also the iPad Pro 2020 is the only iPad to get wifi 6 standard 802.11/a/b/g/n/ac/ax.