leg of lamb was the first thing I ever cooked on my first smoker. IMO it is easier than a lot of other meats because it doesn't get dried out or tough as easily if the temp in the chamber exceeds the target range (the meat however cannot exceed the target temp). In fact I finish mine off with some direct heat over coals to get the bark I am looking for. I usually do a rub consisting mainly of dried rosemary, thyme, Himalayan pink salt, various peppercorns, a few dried chilis all ground up to a fine powder using my mortar and pestle. Then I rub it on the leg the night before. Depending on the mood I am in I may also cover the leg with mustard before putting it on the smoker. That also gives a nice bark. In fact I am getting one ready for tomorrow right now. I will be trying to inject lamb for the first time. Going to use a modified version of thirdeye's injection from the lamb injection thread. If you go the mustard route you def do not need a mop. Also am going to try adding some sweetness today. I have never added anything sweet to lamb before so I am interested to see how it will turn out. I also recommend sandwiches with it the day after. Blue or goat cheese and some onions on french bread.