Of the three different Ti-lite 6's that I originally handled (satin/zytel, black/G10, bead-blast/aluminum), the only one I could easily wrist-flick open with a snug pivot was the satin/zytel. Based on my experience with other black-coated and bead-blasted folder blades, I assume that the black coating, and the bead-blast finish, were creating friction in the pivot preventing a flick-able opening. In any event, I bought the satin/zytel Ti-lites, one 4", and three 6" (possibly more to come, I really like them).
Being able to easily wrist-flick my 6" Ti-lites open (without blade play) is part of the fun of owning them, so it's something that is important to me. It may not be important to others.
I use my 4" for occasional utility use, and it works just fine. If a person were planning on using a 4" for a lot of utility use then choosing one with a higher grade of steel might be worth the higher price. But I regard the 6" as nothing more than a stabbing weapon, and a cool, fun knife to own, so I didn't feel the need to pay for the higher grade steel.
And between the three different handle materials on the 6", I couldn't feel any noticeable difference in grip.