Crazy Nutrition Mass Gainer is the lean gainer of the group. At about 488 calories a serving it's built for adding a controlled surplus rather than dumping 1,200 calories at once, and its carbs lead with gluten-free oat flour for a cleaner base and only around 8 g of sugar. A DigeZyme enzyme blend and MCTs help it sit easier than the heavy bulk tubs.
The honest reasons it ranks low: it's the priciest tub per calorie on the entire list, it's sweetened with artificial sucralose, and there's no creatine. If you specifically want a lighter, easier-digesting gainer for a slow lean bulk and don't mind paying for it, it has a real niche — but as pure calories it's poor value.