Here is my tip currently:
The tip failed after beating the crap out of it. Hundreds of hours on here, no complaints. An old Chandivert Crown, nothing fancy at all.
Here is a link to video of me stroking with this floppy tip:
http://youtu.be/C8Jbrden6vU
(Yes, I missed the bank trying to show more inside off the rail. TOI banks work when you need to open them up!)
All I have to say after experiencing this is that I will giggle at anyone spending more than a few bucks on a tip because "it spins the ball better". I will take another video when I have a moment to see if I can get some crazy juice without the tip flying off.
TL;dr - expensive tips are for vanity