Surprisingly, looking at recent photo's of Circle, the 'main' line up looks to be pretty consistent with the earlier ones. I guess they just like to mix things up a little and have a punt at everything musically (well save dub, house etc...:)
They did that Falcon (ex Circle) album, then followed it with a Circle (Ex Falcon) release, so I guess the Finnish sense of humour is at play in some respects. Oh, they often sing in a made up language too, think it was called Meronian or something (kinda llike Magma in that respect).
I (well my wife spotted them first) jumped on the bandwagon during the Prospekt period, when they did a short tour with Acid Mothers Temple (2001/2?) caught 2 or 3 shows and have been a fan ever since. Those gigs were amazing, they locked in like no other band I can think of (possibly Boredoms live) and the sound was feroucious, plus the singer/keyboardists 'Rob Halford-isms' added a touch of hilarity. Saw them with Guapo around the Five Suns period, that was wonderful too. Guapo rocked live as well, they had a drummer at that time who was something else.
As I mentioned in the list, not everything is to my liking, but god bless em' for trying. You're never sure what you may get, and I like that.