Waternan Hemisphere Problems

I was bought a Waterman Hemisphere for xmas. Normally I use Lamy
Safari, Cross or Parker fountain pens so I am well used to fountains
pens when they work and when they dont.

I decided to wait until the Waterman ink converter arrived from the
Parker Pen Co. I then filled it with Noodlers Purple. The first 2
pages of A4 were OK, but after that the ink was having the devils own
job getting out of the pen. I was really having to press hard.

I emptied and refilled the pen a couple of times and got the same
results.

I thought that the ink might not suit the pen so I cleaned it out,
dried the pen and refilled with Mont Blanc black, an ink that is not
reknowned for being a good one in the reviews. Again it wrote two
pages but you had to press hard on the nib.

I passed the pen to the better half and she usually writes with a
fountain pen. She too was having problems with the pen and said that
she was pressing much harder than usual. Is this one a lemon or is how
Watermans are. The review that I have read gave higher marks to the
Waterman than to Mont Blancs!

Thanks a lot

Andy