PrimoPDF PDF print driver

Just tested PrimoPDF v3.0. It seems very 'light' in the sense of non-intrusive and ultra intuitive and easy to use, however I was trying to 'print' a short piece of choral stuff - four pages of SATB with a descant staff and the lines on the staves were of uneven weight which made the output look very weird. More specifically (all lines counting from the top of the staff): The fourth line of the Descant staff, the second and third lines of the Soprano staff, the first line of the Alto staff, the fifth line of the Tenor staff and the second and third lines of the Bass staff were all 'very heavy' - difficult to judge but at least double the width of the 'normal' ones. Also roughly 60% of the bar lines were of the same 'heavy' weight. There seems no pattern to it - it is not even concistent between one page and the next and it throws you somewhat.

I shall be looking for another PDF printer. Looking sadly though because apart from this one issue, Primo PDF is one of the best pieces of software that I have used (I'm an ex-Managing Director of a software house). The inconsistent weight of the lines is just too much for me - might be acceptable for others.