Replaced by the HF M400, but still an excellent camcorder if you can find it for a decent price. Here's what we had to say about it back in 2010:
A nice blend of technological advancement and idiot-proof features, the HF M300 is a reasonably priced HD camcorder option from Canon. The M series is characterized by advanced add-ons like Smart Auto mode, a 15x HD video lens, Touch & Track focusing, and video snapshot options. The M300 is the "budget" offering from the M line; it's almost identical to the more expensive M30 and M31, but it has no internal memory. With the M300, you have to record directly to SD cards. For most of us, who have gotten used to the idea of memory cards as internal storage has gradually disappeared from most still digital cameras, this is hardly a sacrifice.