I've got some PacSci 253 oz-in motors for my Xylotex. I've ran them, but I don't have my router built yet. They are rated 2.3a series. The trade off is parallel wiring will give you more top speed (actually more torque at high speeds, which translates to higher top speed). Series will still give you full torque at low speeds, but you won't be able to go as fast.