Safariland: Pluses...easy and fast to load with; works with the natural inclination to push harder when in a hurry; more compact in standard form than HKS; better for loading with the off hand or one hand only. Minuses...rounds are not as secure if dropped onto a hard surface; very weapon specific due to method of release; more difficult to initially load cartridges into loaders; do not work well with some pouches; will almost always fail if barrel of loader breaks.

HKS: Pluses...made for a wide variety of revolvers; easy to find in any well stocked shop or at a show; fast enough with practice to rival Safariland, but they DO require more practice to get there; ammo is very secure, even if dropped onto a hard surface; will often continue to work fine even with a broken "barrel" (I have seen this many times); much easier and less trouble for range use with large numbers of shooters when loaders will be used for most reloads over and over again. Minuses...larger (taller) than Safariland loaders; require the knob to be turned rather than pushed, which thus requires the cylinder be held in place while loading; less off hand or one hand reloading "friendly"; can release ammo if grabbed by the knob and inadvertantly twisted as they are taken from a pouch. (seen that many times also!)

I prefer the HKS, mostly because I used revolvers for many, many years as a duty sidearm and prefer reliability to a slight increase in speed. I tried more than once to switch to Safarilands, because in theory, the basic design should be great for duty use, but they just never gave me the same rock solid reliability and good service the HKS's did.