First up, spacer kits. Spacer leveling kits are nothing new, and are a trusty and popular way to get some extra front ride height out of your truck. Spacer kits add some extra front lift without too many hassles and usually keep your truck's street ride near stock. They're also extraordinarily inexpensive, with most kits costing several times less than a full leveling shock/spring assembly or coilover kit. They do, however, have a couple of issues. The biggest problem with spacer kits is that they are not a performance improvement. Spacers "only" add front height. They don't improve rebound, response, articulation, or ride quality in any way. The other issues common with spacers include: Bouncy turning; some extra NVH (especially with metal spacer kits): and a few kits actually require you to cut your truck's factory studs. Basically, spacers are a good choice if you're on a budget and aren't really going to be yanking your F150 around too hard on the street or off-road.
So now we come to leveling shock assemblies and coilovers. These kits are our preferred method of raising front ride height due to the fact that you usually get improved suspension performance out of strut and spring or coilover leveling kits, unlike typical spacers. Most loaded shock/spring kits and coilovers are extremely easy to install and drop right in place of your factory hardware. Coilover kits are especially powerful and are basically the "go-to" systems for getting improved off-road performance. These kits also give you plenty of ways to further improve your truck, such as: Improved rear shocks, UCAs, rear blocks, and other hardware to get even better performance. Still, these systems have a few drawbacks. The main issue, of course, is their cost. Even the most basic shock/spring leveling kits are double the price of the simplest spacer kits, and more capable hardware can clear out your piggy bank very quickly. While we agree that coilover kits improve performance, their abilities can vary from one extreme to another, as well as different brands and types. It's extremely important that you do your research and find the system that meets your needs. The last issue is really only for really powerful off-road coilover kits which is that it's not uncommon for those systems to stiffen up the street ride of your truck. We wouldn't call it "bad," but there's a noticeable difference. It's like being in a car with a basic lowering spring kit. If you're expecting a baby smooth ride, you're not going to be very happy.