i have a gcw zero. not sure i recommend it. I love everything about it, except my d pad's up direction is broken. And the system is new. Im going to get it modded by a service i found on facebook, and hopefully with a ds d pad in there it will be a great system. if you dont plan on modding the d pad, be wary that the d pad depending on your luck can be god awful.
Also, for 150, the gcw zero is a pretty poor value. The system feels cheap, but at least it has a nice design. It's just the system feels more like a 50-80 dollar system, not 150... I'd give the gcw zero a 7/10 with the faulty d pad. I love the size and simplicity of the thing, despite feeling a little cheap. Too high of a price. If the d pad mod fixes the dpad, i'd give the gcw zero an 8.5
The emulation is solid, and getting games on it via sd is lightning fast and easy
literally drop games in a folder on sd and youre good to go. No hassle with the emulators.
The screen looks great for some things, notably genesis, but for snes, because of the funky screen dimensions of the system, if you put snes in fullscreen, you will have uneven pixels where 1 line of pixels is sharp and others are blurry. It isn't too noticeable, but is indeed a bother if you prefer pixel perfect graphics. Although, you can just set emulators like snes not to full screen to fix this, but then the screen is a little small.
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I also have a gpd xd. It's an android handheld. got it for 133 dollars on ebay new in box. Now that system....I'd pay 250 for it. It is extremely high quality, plays dreamcast games with perfect-near perfect frame rate. But it's an android console, and you need a google account if you plan on purchasing the high quality emulators for it, like epsxe (ps1). Although, I give the gpd xd a 9.7/10.