David,
I have a guru and only use it on the occasional overnight when weather conditions make me cautious of holding a temp all night with a MM. Usually, regardless of the weather temps, as long as the wind isn't strong and it isn't raining, I go with just the WSM. I love the guru for what it does but I find it overkill under most conditions. The WSM is amazing all on it's own.
I have a guru and only use it on the occasional overnight when weather conditions make me cautious of holding a temp all night with a MM. Usually, regardless of the weather temps, as long as the wind isn't strong and it isn't raining, I go with just the WSM. I love the guru for what it does but I find it overkill under most conditions. The WSM is amazing all on it's own.