I know for a fact that the Makita 3612C has the 1/2" collet, it also comes with a 1/4" reducer sleeve to use with 1/4" bits. I believe that there may be metric "sleeves" for the Makita as well, in case metric bits are available to you. In fact, some area's only deal with metric. The Bosch, I think has both collets or it may be similar to the Makita, uses a reducer sleeve. Bosch and Makita are both excellent routers. I'd say, you can't go wrong with either of them.
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