TNT is a extruded with fluorocarbons added in, not sintered. I have a lib with a TNT base and one with a sintered base. One is not noticeably faster then the other, but the sintered is much harder and does not get gouges as easily, but the sintered also drys out much faster and needs a wax after every couple days, and when it is gouged it is harder to repair, ptex candle will not stick.
so pick your choice, TNT, softer but is easy to repair and requires less maintenance, or sintered with gouges less, is harder to repair, and requires more frequent waxing.
I own two libs so i dont think im a lib hater.