Since the optics and sensor are the same on the TM300 as the HS300, video performance should be identical. Unsurprisingly we couldn't see any differences, which is no bad thing as the HS300 shoots excellent video. The Panasonic shoots a slightly more naturally coloured video in good lighting than the Canon and Sony competition (although Canon provides settings to dial this back if desired). Detail is excellent, too.
Low light performance is noticeably better than the last few Panasonic HD camcorder generations. Colour and brightness are maintained to impressively low levels of illumination, without much sign of grain, so there's still plenty of detail, too. In comparison, Sony's HDR-XR520 has a slightly darker, but still very impressive image in the same lighting. Canon's LEGRIA HF S10 shoots slightly brighter footage, but with a little more grain. It's a matter of taste, but we still slightly prefer the Canon's performance in very low light. There's not much in it, and Panasonic's lens ring, full-sized accessory shoe and lower price provide more than enough compensation.
The Panasonic HDC-HS300 looked like a hard act to beat when we reviewed it, but the TM300 is an even more attractive package. The smaller video storage is balanced out by the reduced weight, and it's around £50 cheaper too. Although Canon's LEGRIA HF S10 and Sony HDR-XR520 are brilliant camcorders too, the former is considerably more expensive and the latter doesn't offer the TM300's manual control. If you're serious about your video making, the HDC-TM300 gets the balance just right between features, video quality and price.