I have Aaron Lankford's tape. I remember it as being the first "real" kickboxing tape I got, and my favorite for a long time. Great form tips. No choreography (which I don't want in my kickboxing). As intense as you want it to be. As someone else mentioned, it IS rather dated. And the bright red "diaper pants" on the two background exercisers are infamously funny!
As for Powerstrike 3: It is not as immediately intense as 1 and 2, and has more of a build-up to intensity than those two. But I like it for that very reason. I can really focus on form and intensity (I also use weighted gloves, but have worked up to that). Unfortunately, 3 is the only one on DVD.
Even more intense, IMO, are earlier Powerstrike workouts. About a dozen in all, from different "series." They are difficult if not impossible to find nowdays, and the camera work and sound often leave much to be desired (their first video was almost nauteating to watch: so many quick camera changes, like someone's 12 year old brother got a video camera for his birthday and wanted to try it out), but the workouts are excellent! Illaria is a black belt in at least one discipline, and she brings authenticity to the workout. The rapport between Illaria and Patricia is very good also. A few people have a hard time understanding Illaria because of her thick Italian accent, but I like it (and I have a good ear for accents).