I'm looking to replace a NV4116-HS with a 5xxx series NVR, mostly because I hit the 80Mbps limit (guess I should have planned better). I see under different brands there are 5200, 5400 and now 5800 series. The last two digits indicate the number of channels it can support, but are there hardware differences between the different 5xxx series? Or is it just the firmware which is running? I see Andy sells the NVR5432-4KS2 32. Is this better than a NVR5232-4KS2? Is there any reason to try to by a 58xx?