It's essentially the same from the same OEM manufacturer but comes with re-designed case, SD card slot, power switch and 2 year hardware warranty - Otherwise the same operation and the same firmware can be used between each other though will require the folders being renamed/moved a little.
EVO NOVA Twin = 2 x DVB-S/S2 tuners (as per H.2S)
EVO NOVA Combo = 1 x DVB-S/S2 + 1 x DVB-T/T2/C Hybrid tuner (as per H.2H)