In January of this year, I ordered two Pentel Pulaman disposable fountain pens. One with red ink and one with black ink. (They also come with blue ink.)
I was definitely surprised when it arrived. The nib is plastic and I wouldn't actually describe it as a fountain pen at all. It's more like a felt-tip pen, but the plastic tip lets it flex a little bit.
Overall, it's a fine pen, a great writer and very inexpensive. It's just not a fountain pen.
The red ink is bright and clear, the black is very dark and opaque. When you write with it for extended periods of time, you can catch the tip of the pen and end up with a bit of splatted on the page...just like a fountain pen! It's such a funny little pen in my mind. The term 'fountain pen' just does not accurately describe it.
My husband has adopted both and he really, really loves them. They are his go-to pens right now. His other favorite writers are the Parker Challenger Fountain Pen and the Cross Affinity Fountain Pen. He also really likes the Disposable Pilot Varsity Fountain Pen.
We've used these pens on Muji Notebooks, Moleskine Notebooks, scratch paper and 25% cotton paper. All take the ink just fine and no bleed seems to exist.
Final word: Great, inexpensive, disposable writers. Not fountain pens!
Are you into Disposable Fountain Pens? I wrote about three more disposable fountain pens here: The Pilot Varsity Disposable Fountain Pen, The Pilot Plumix Refillable Fountain Pen and the Bic Disposable Fountain Pen.
And a total dud of a disposable fountain pen here: the Dodec Disposable Fountain Pen.
PS: Images above show testing on Muji Notebook paper.