Sharing my experience with Edifier speakers for my 2011 Honda City, on stock head unit.
Wanted to go for NF651A, as it sounded really good to my ears, on headunit power, comparable to other brands at a higher price.
However, the tweeter was quite large and it didn't fit into normal tweeter pods and I don't want to do any custom installation work (intend to sell the car in about 2 years time), so I had to look at other models.

I then went with GF651B. Of course it wasn't as good as the NF651A, but for casual listening, it was quite good. I'd say it is value for money. I chose it because it sounded better than other brands for about the same price (RM300 range), and the tweeter was smaller, and had different cups/fascia depending on how you want to mount it, in my case, surface mounting on dashboard. Speaker wires included were reasonable in quality and long enough, and crossovers were also separate units so you could bi-amp them if you like.

Basically everything I needed was in the box, and I just had to buy speaker ring adapters for my City and I was good to go. For my listening tastes, I set the tweeter crossover to -2dB (there was 0, -2 and -4), and I'd say I'm satisfied with it. Headunit flat EQ, and all my Spotify songs were enjoyable.

Of course, if I did sound proofing, put in an amp, change headunit etc etc, it would be better. And definitely the NF651A sounds much better. However, for the intended usage and purpose, I'm happy with it.

Disclaimer: I was not incentivised in any way to share my experience. I paid full retail price for the speakers and just wanted to share my experience with this speakers, since I couldn't find much info online and I don't read Chinese (I suppose one can find more info on China forums etc).

Our first 8" underseat subwoofer will reach on this month.

Not really, the height of RW8 is around 7.81cm only.
Stock will reach on this week and you can install as many units as you want because it comes with sub output port for connect to another sub.