Where are you from Timmy? Mesquite is great for smoking, grilling, fireplaces, campfires, and everywhere else you want a long-burning clean wood.
The people who say mesquite is too harsh, bitter, creosoty, and so on most likely pile it on when they don't need to. Mesquite has been used from texas to Arizona (and alot of other places) for centuries as a grilling and underground pit fuel. A little goes along way with mesquite. If you plan to do a stick burner smoker with mesquite, you need to build the fire well in advance to bank up some coals. Then add just a little stick wood as you go to maintain the fire. Mesquite lump makes it a whole lot easier than sticks.. but it should still be pre lit before adding to the firebox..