I've just got one of these Aventura pens for everyday jotting and doodling.
I really like it. It's got a really nice flow, no flooding but lush regardless, nice balance, and I think it's well built - I can't fault the cap action on mine and the lightness is great for keeping it in a breast pocket
It didn't come with an adapter - it's obviously a cheap introduction to Cross pens, which again suits me as I tend to lose pens quite easily.
I would also like to know which adapter fits it. I suspect that neither does.
So I'll be re-filling cartridges where possible because I have a large amount of cheap similar size cartridges that don't fit - I was using Rotring pens but they wore out rather too easily.
This is the best pen I've had - easily better than Parker ones for a similar price.
Anyway it'll get quite a rigorous testing regime in my hands so we'll see how it copes.