Most people will recommend
Replay Media Catcher (RMC) over
Jaksta. However, I can tell a different story. Which program is better for your needs depends on your system and the sites you want to capture.
For example, I achieve the best results on Stickam and Smotri with
Replay Media Catcher]Replay Media Catcher (RMC) but with
Jaksta on BlogTV and JustinTV. Unfortunately RMC locks my browsers after some time of usage which can only be solved by a complete reboot while Jaksta runs stable as a rock.
Another thing is, I read everywhere that RMC's support is supposed to be superior. However, my experience is different. RMC support simple stopped answering at some point while the guys at Jaksta answered all my emails and even provided me with a beta version.
Both programs come with problems and annoyances but in the end Jaksta is my favourite.