It is distressing to see that you have had a 'bad time' with Novatech. This is unusual for them. However, reading between the lines a bit, they did accept that their service had been less than perfect and went that bit extra to keep you happy. That I would expect from them.
You do seem to have drawn a bit of a short straw in that reliability was not up to their usual standards and the did replace the machine. Perhaps they didn't reply to emails in order to avoid a confrontation?
I have had friends that are extremely happy with Novatech. More than have been unhappy.
I have been using Novatech virtually since they started down in Hampshire and have had many transactions (including my latest laptop and desktop computers) - all without difficulty. In all the years I have been using then, the only faults I have had were a duff usb lead (replaced without question) and a usb multiport which died after about nine months (and they popped a new one - better quality - immediately by 1st class post and without wanting the old one back).
If do a search through the forum, there are far more bouquets than brickbats. You seem to have been an isolated unlucky customer who they have done their best to keep happy.
And no... I don't work for them.