1/4 or 1/2 Shank?

Yes , and they don't really cost that muct more,I use 1/2" when ever posable.O,K,
Learning Herb

1/2" shank bits are stronger and have less vibration than 1/4" bits. Cost is usually about the same. Make sure you get a decent quality bit, the few extra dollars will save lots of heartache later.

Who says you can't have both? Bosch, PC and a whole lot of others have both 1/4" and 1/2" collets for them. In fact I also have an 8mm for my Bosch plunge router. On average, the thicker the shank the better. Less vibration & chatter while cutting.

Hi Jamin: most people have both 1/2" and 1/4" bits, because the bigger shank cuts vibration and usually gives a better cut. However, bits that are used to shape edges
and take light cuts can be easily done with the 1/4" bits. When you use big bits
like those used to cut rails and stiles for doors and raise panels you use 1/2" bits and slow down the router speed. These bits remove a lot of material, and absolutely should be 1/2", 1/4 " bits if they are made in those sizes should not even be bought because they are dangerous. As to quality, cheap bits cost more because you will have to replace them when they fail. I suggest you buy the best that you can afford
good bits last a long time and will take sharpening more times in thier life.
Hope this helps...Woodnut65