I would agree with Slayerverse98, it was the Buffy range that got me really hooked on Sideshow 12" although I had already started to collect the Bond figures.
Over time I have added the X Files and Highlander figures, as well as some Universal monsters to my slowly expanding collection as Buffy releases have slowed down somewhat. I also have one premium format figure and some statues. I have no doubt that I will collect some (probably most) of the Star Wars 12" and selected premium format LOTR (I have the 3 NECA 18" figures and for the price, they are awesome.)
However, I do have one rather major whinge. Do Sideshow have a problem with authority figures? We have a Q, but no M (or Moneypenny) in the Bond range, we have Mulder and Scully but no Skinner in the X Files range and most importantly, (especially when you read this thread and see how many people were originally drawn to S/S by Buffy,) we have no Giles. I believe Brant said he was "top of a list." Well please get him off the list and into the box! Before Dave tells me he won't sell I would check any forum relating to S/S's Buffy line and the absence of Giles is a major complaint.
I have an "ancient" Playmates Star Trek 12" collection which is incomplete because one crew member was never released. I have a major fear that my Buffy? Bond / X Files collections will end up similarly scarred!