I don't have direct experience with that particular machine, but I believe you will get exactly what you pay for.
It's MDF construction. Humidity and moisture causes many problems with that material and it isn't ridged enough for the stresses it will be subjected to. The MDF looks to be 1/4" - 3/8", most likely metric dimensioned.
Looking at the assembly, the MDF is intended to hold the backlash nut in position.
It is belt driven and that has it's own issues. The combination of belt drive, along with MDF construction, don't depend on it having good resolution or repeatability.
For the price, and if you run it slow, and don't mind constantly working on it, it might work for your intensions. I personally would save for something of better quality.
If this is the rout you want to go, I remember a Joe's cnc in the classified. It is also MDF construction.
It's your "hard earned", as you say. It would be upsetting spending it on something that isn't satisfactory to your intentions and either toss it in a corner (money wasted) and give up on cnc, or have to invest in a better machine after the initial purchase.
Sometimes cheap is exactly that, and cnc isn't where cheap exists.