Replying to all your posts I never said the ultimaker was a terrible machine, but was annoyed at how long after sales support took to handle these matters, and after calling and persisting I got a new heat bed again, therefore this is the third fitted on my machine in just four months.
I questioned the reliability of the machine in general or perhaps the heat bed more specifically as I'm already on my third...
I also read some comments with too bad, easy to fix, and so on... True but none were in fact clear of what one should do exactly. One also had blown tracks on the element circuit which wasn't my problem. I also got a link from someone who changed ptc to another type and went through quite a lengthy and useless process, as all you need to do is change it with the correct part number.
In my first problem machine would stop during a print so thermistor had an intermittent problem, due to a faulty ptc.
I'm quite familiar with electronics, and after checking both heat beds the problem was in both cases a faulty ptc100 which is mounted on the bed. This is quite straight forward to desolder and replace and also available for $10.00 a piece true, but to remove bed, desolder and replace and refit and level glass is quote a job to be done on a regular basis.
I just hope this head bed doesn't fail again soon, and thanks to Ultimaker for helping me out once more.
I did shop around before buying and I also know other machines also have their own problems, and still wish to believe the ultimaker II is a very good 3d printer, just hope it's built to last. Time will tell...