You really shouldn't "grind" the tip down. They're plated so that solder sticks to them. If you grind the plating off, you've ruined the tip.

If you're willing to invest a little more, both Weller and Hakko have some cheaper stations down in the $85 range. The ability to get replacement parts (and tips, etc) from a variety of sources is pretty nice when you go with a larger name brand.

One of the best features of my Weller station is it heats up to temperature in about ten seconds and cools nearly as fast. There's no waiting around.