The bad feedback from the Eonon unit is mainly because of the pop on bluetooth connecting, and some volume issues with music playback, but there are ways around that. If you play your music through bluetooth, then the volume control is fine because you have volume control both from your phone and the unit, and through the combination of the two, it's fine. Also with the loud "POP" on connecting to bluetooth, it only sometimes happens, and doesn't happen if the volume is low?
To me the disadvantages are far outweighed be the advantages

It's great for its price tag.
Another thing to keep in mind, if you're wanting to run the oil pressure gauge, you're going to need to do the spin on oil conversion. This is because you need an adapter plate to run your oil pressure sensor from and this goes between the block and a spin on filter...
You can get the adapter plate from prosport too, but you can pick up ones off eBay for a bit cheaper..
You can also get the spin on conversion from the vendor @
EdgeAutosport.com on here, I got mine and iirc it was about $60?...