[FYT Android Head Units] COASTER19:
What I mean is that at 1024x600 resolution, a unit as powerful as the PX6 should absolutely fly. It's theoretically far more powerful than my phone in every way but is a stuttering mess to use in reality. It's 2x the CPU power of my android TV which runs perfectly smooth despite being 4K. The biggest difference as far as I could tell from benchmarking was slow flash. Any app takes 10-15 seconds to launch, and my unit didn't come with a fan which made it even worse in the Texas summer (I've since added one, it was absolutely 100% required to make it usable). Other users here with PX6 MTCD/E units tend to have a different case and heatsink design than mine came with which includes a fan stock. It does appear to be a genuine RK3399, but definitely not the same application circuitry ("coreboard") as is most common on MTCD/E head units. Oh and all apps also crash to the home screen randomly about once a week. Part of why I'm interested in this unit is to look deeper into this PX6 behavior on the bench rather than in the car. I wouldn't be surprised if there's a thermal pad missing from a storage controller or similar part causing throttling that the OS can't detect.

The Hal9k v4 ROM paired with 32 bit apps helped with the speed a lot, but it still doesn't feel anywhere near as fast as my $100 Umidigi phone with a MTK Helio P23. More importantly, Hal9k v4 allowed me to control how the unit sleeps.

By default the PX6 "Auto Sleep" mode will kill all apps except the launcher and stock music player when you turn off the car. When you turn it back on the unit wakes from sleep instantly, but apps need to be restarted manually which takes those 10-15 seconds to load the app back into memory. With the custom rom, I currently have Tasker, Google Maps, and Spotify always kept in memory, even during sleep. That way Spotify music or navigation can resume playing within seconds of turning the ignition. This is a feature I really don't want to lose unless app startups are drastically improved. I'm perfectly happy automating it with tasker if there is a way to prevent only tasker from being killed though.

I'm aware of the Teyes CC3 flashing threads on 4PDA, but the translation is a bit unclear and I haven't found any in English on XDA. I'd be super grateful if you could link me to one. I'm happy to work through it with translate, but also don't think I need a launcher system as complex as CC3. Joying would probably be a better bet. My ideal setup wouldn't even include a launcher, just cycling through a few apps with the steering wheel controls. And with all of these flashing options I worry about configuring CANBUS settings correctly, as it took a lot of experimentation on my PX6 to get them all working correctly in Hal9k. I would really prefer to be able to take a NAND backup and restore through recovery or a SP Flash Tool equivalent. With PX6 that's not too difficult since the recovery is well documented and there are many rom options (including one direct from my aliexpress seller).

I decided to just buy it and find out for myself, these FYT Navifly units are surprisingly cheap for the power, and worst case I could probably use the QLED screen to upgrade my PX6 display since the form factor is identical (the PX6 motherboard has lots of display connectors despite the coreboard deficiencies). I also believe these FYT units are more capable in CANBUS support, potentially allowing me to use my car's stock radar sensors rather than just the aftermarket AHD backup camera. They also appear to detect when doors are open, seatbelt unbuckled, etc. My PX6 CANBUS only supports some of the SWC buttons + headlight state for dimming.

The PX6 CANBUS also outputs song names to the stock driver HUD somehow, though I don't care about this feature at all as the HUD will never be useful unless I return to the stock Audi RNS-E head unit where it displays directions. But that thing required you to type by scrolling a dial through each letter of the alphabet one by one. No touch whatsoever. There's a wonderful Top Gear clip of James May trying to work out how to use the same RNS-E unit in a Lamborghini and it is just as awkward to use as they make it look on camera. The PX6 is so close to being what I want, and in terms of software features it is perfect as far as I'm concerned. The hardware just makes me feel like I'm trying to run android 9 on a phone designed a decade prior intended to run froyo.