After running this box for a while now. I have to say its pretty good. Doesn't crash , works fine on both cable and satellite sides. Easy enough to use for family main viewing box. In fact I previously had a dm800se with cable tuner and a vu duo with twin sat feeds as my main viewing boxes.
I have now removed both of them and replaced them with the zgemma with a 1tb WD passport USB drive attached for recording.
I don't think this box can be beaten in this price range 73 quid delivered, from uk suppliers with uk 3 pin plug as standard.
I haven't noticed any speed issues either it's perfectly usable and stable. Obviously if you compare with a high end more expensive receiver like a vu solo 2 etc you will notice a speed difference but considering those are double the cost and have dual core CPU's its not a fair comparison.
In terms of weight and build quality they are a lot lighter than say a DM 800se clone, the remote is a lot lighter as well. Long term reliability is yet to be determined. But for the price perfectly acceptable.