C-Forum

I'd like to hear from folks who have some experience with these specific boats how they compare in terms of stability (primary and secondary), handling, and water types. Thanks in advance for your input.

Probe 11 has more primary and secondary stability than the Outrage, though is perhaps a wetter boat. Probe 11 makes an excellent beginner boat and is easy to surf. Outrage has more acceleration and glide, and quickly teaches you good balance in a boat. Probe 11 tends more to the playboat spectrum, Outrage more to the river runner end of things.

Probe 11 is a great beginner boat, but you may outgrow it relatively quickly. Outrage will put you in the drink alot at first (if you push it), but will soon make you a better paddler. I'd put my mother in a probe, not an outrage. If you like to push your limits, the outrage will allow for more growth(and fun), but will make you pay a price if you're not on your toes. two very different boats. happy hunting.

does 4" difference in length really make much of a difference?

There's so much more to a boat than length. What we're looking at here are two very different hulls.

I never tried an outrage, but I did try the probe.

The probe is very forgiving, very beginner friendly, and not a slow accelerator either. Though the boat is kind of wet. If you paddle continous class III, you'll probably have a problem keeping it dry.

If you don't mind the steeper learning curve, you could also consider the viper11 (that's what I'm paddling). that is said to be an upper-intermediate to expert level of boat. Now I'm far from expert, maybe lower intermediate and I paddle a viper11 on class III, or at least I did last summer.
The viper is more strict in the way you paddle it, it's more "severe" less forgiving. But it's not a boat that punishes you for every minor mistake in balance or lean. But the viper is definetly drier then the probe and you will not outgrow it as fast as you probably will with the probe.
From what I'm reading here, the outrage has similar advantages/disadvantages over the probe.

I'm not telling the probe is a bad boat, absolutely not. I like to paddle it as well from time to time. It just depends on how you want to learn, how fast, how hard, and how hard you want to take the swimmings in your learning path .