On a good HD TV, with a broadcast of HD material, typical Freeview HD is a significant improvement over typical standard SD Freeview.
This is for 3 reasons:
1. HD having many times the resolution of SD.
2. Freeview HD using a superior compression algorithm, which gives higher perceived quality than standard Freeview even for the same bandwidth and resolution.
3. Each Freeview HD channel being given a lot more bandwidth than a typical standard Freeview channel.
If one compares one of the higher bandwidth standard Freeview channels, like BBC1, with a Freeview HD channel, the differences is less pronounced, but still there. This is because a good proportion of the terrible picture quality of a typical standard Freeview channel is because it is being squeezed into inadequate bandwidth for commercial reasons (more channels = more £££), but so far, at least, the Freeview HD channels have not been treated so badly.
On the subject of Humax, I've got their Freeview HD recorder and I'm very happy with it. It has the occasional glitch, like all computers running complex software, which is what a digital TV receiver basically is. I actually think their software is relatively minimal and elegant, properties which usually lead to low bug counts. Also, for people who like to fiddle with their consumer electronics, as I do, there is a thriving community of tweakers, providing such things as unencrypted backup of HD recordings. See
http://hummy.tv/forum/ for more details.
Kind regards
- Garry