-- Last Updated: Jan-22-13 12:21 PM EST --
The fact that you are asking whether these distances are reasonable makes me suspect that being able to recover after a capsize is probably a skill you still need to work on. Naturally the best method is a roll, but even re-entry should be practiced. Naturally you don't want to find yourself unable to get back in the boat when miles from shore. Also, it doesn't always take much wind to make a partially swamped boat move pretty fast, so you should have the experience that helps insure that you not let go of it in such a case. You don't want to let go of the boat and then notice two or three seconds too late that the wind is taking it away faster than you can swim. Of course, you'll be carrying a load of gear (making a wind-blown boat slower), but then, the wind may end up being stronger than you wish as well. The kayakers here (I'm not one) can say more about these and other safety issues.