I never played any of the JPs back in the day, although I was interested in them and wanted to play them since. I bought Pegasus Prime from the summer sale and have played it so far probably to the half way mark or little less. I must say that it is one wonderful game and after playing it for a while, I had to get the JP2 and JP3 also. For three bucks in the sale, they were a no-brainer.
According to the reviews JP2 and JP3 are far superior to the first one (or the Pegasus Prime remake available here on GOG), so I'm quite sure that will get some fun hours with the sequels also. They don't make games like these anymore.
I need to get 2 sometime definitely. Even if I have to snag the disc version.