The motors arrived from Hobbyking on Wednesday...one of my quickest delivery times.
As you can see, the outrunner is a lot smaller and lighter than the inrunner. However, I don't think weight will be an issue and it's only about 25g (1 oz.) difference so it will really come down to performance and longevity.
Neither motor comes with connectors solders on, but the outrunner does have 3.5mm bullets included as well as some heatshrink. So it's not only cheaper but it will save the cost of connectors if you use them. I used my standard 4mm silver bullets so if anyone wants the unused 3.5's let me know.
I've spent the afternoon converting an old model to accept these motors and will hopefully get out for a few test flights tomorrow. Brief test runs with a APCe 5.5x4.5 and an uncharged 2200 mAh Turnigy Nano-tech 35-70C pack gave 40A for the inrunner and 50A for the outrunner. I didn't measure voltage, but assuming 11V this equates to 440W and 550W respectively. My concern will be that the outrunner will get too hot and burn itself out quite quickly. Time will tell.