The answer to the question about whether triple glazed windows are better than installing the usual Double Glazed Windows is not that simple as it depends upon a few factors, some of which rely on the priorities of the person who is thinking of installing them in the first place.
In terms of outward appearance there is virtually no detectable difference in the way the replacement windows appear as the triple glazing is just not visible. However, when it comes to how the windows perform and what they cost there is a defined difference.
Triple glazed uPVC Sash Windows, will almost always (excluding any special offers) cost more than a typical double glazed equivalent simply because there is more glass and they are more complex to manufacture.
But the balance is that triple glazed windows will also reduce noise pollution way more and they will also drastically reduce heat lost via the glass panels – in any event, the question is really, will I save more money by reduced energy bills in the long run by installing triple glazing than I would have saved in the short term by using double glazed windows?