I live in a fairly good reception area but occasionally some channels do block or the audio clicks.
I'm only using an old On Digital box at present but can someone assure me that the Topfield is far less likely to give me these problems?
Thanks in advance.

I'm not sure that anyone can really provide you with that assurance, for any set-top box/PVR.

What I can say is that I was the user of an original Pace On-digital box prior to buying a Toppy. I had occasional intereference/break-up (possibly for a few seconds, once a week?). With exactly the same aerial setup, my Toppy's reception is the same/perhaps slightly better. I certainly don't find the tuners wanting in anyway...

Likewise, I would frequently find that my Mux2 signal broke up, especially during the summer, on my Pace OnD box, but it's been rock solid with the Toppy.

Nigel.

My 5800 works very well on an indoor aerial I also have a DHD4000 which also works very well however i had a Fusion FVRT100 who’s gain was very poor, I would say the 5800 has a good gain and performance.

My Philips OnDigital STB worked OK with occasional minor break-up. When I got the Toppy it wasn't at all reliable until I'd paid some attention to the aerial down-lead (had installed a new wide-band aerial shortly after moving in). Had quite a few missed recordings with the clock becoming inaccurate (by a magnitude of years!) and timers getting deleted before the allocated recording. However, this problem has apparently been resolved with recent firmware upgrades giving the clock greater resilience to erroneous time signals.

No picture break-up with the Toppy just the time signal problem above. Resolved by removing a passive split from the down-lead.