You really think boxwave is spending R&D to create two different rubber tips?
Seriously, I'm not trying to diss on your stylus. I've spent my own $ on all the styluses I've discussed, and I thought it would be useful for others to know that I've found the one form stylus-r-us to be the best. Maybe you should try it and compare for yourself.
On a side note, I'd like to highlight (again) that I do not use a protective screen. This could be a reason why your tip doesn't seem to grab as much. I used an anti-glare screen for awhile and the finish was definitely smoother to my touch.
Again, just my two cents. I don't mind you disagreeing with me, but I'd rather it be on the basis of an actual comparison. That's at least what I based my own comments on.