Just getting around to putting Jimmy packages together for prospective publishers: here's a pen & ink / color comparison from my bios. This was actually done with a brush, as I just can't ever be happy with sketchbook pro inks.
Something of interest, there's now a photoshop knock-off that you can use for free on your browser. Give it a try, it's pretty great! It doesn't have touch sensitivity, but hell, it's free and available to everyone, everywhere!