Pretty spiffy. Stippling works well for many subjects. May I suggest either pumping up the contrast (by adding some dots to darker areas) or next time using subject material that has more contrast in it? The Mosquito is well rendered but it's feint. Perhaps that's just the photo but whenever I'm working on a drawing when I think I'm getting close to done, I squint my eyes and look at it - I should be able to make out the subject from the background easily. If I can't and can only see random shapes, I go back and work on it 'til it looks right. (obviously this doesn't work 100% of the time but it does for works that are "of a subject", like the Mosquito)
Hope you don't mind the critique. It's well done and very close to where it should be IMHO.
Next you should try scratchboard.
Edit: Man, you swing for the fences don't you? Both those other prints will be very difficult to copy. Lots of subtlety in both... I'm a Remington fan and I've always loved that Reflections print... Hat's off to you. Post it/them up when you're done, I'd love to see how they come out...