I was wondering if many people use the advanced lifestyles from the Runner's Companion?

We do. It adds some depth to the non-running portion of our characters.

It´s optional for us, with almost complete opt-in.

Same; if folks want to specify, they can, if they want the basic lifestyle in the BBB, it's all good as well. I always use it, personally, on my characters. Adds lots of color.

Awesome! I was hoping that was the general feeling. I think they're great.

Optional but all the players in my group are using it. I like them since they add a lot of color/flavor to a character. Just double check to make sure a player doesn't try to abuse them. There are a couple of options that can make the character a down-time monster.

Ditto here. All my characters are using it. It adds a lot of flavour to the game, but I agree with InfinityzeN that the GM should be wary of some of the options (Feng Shui, Resonance Pool) and only grant them under special circumstances.

The addition of the Lifestyle options also makes running game scenes at the player's residence a much more viable option since the location has some "quirks" about it, rather than just the "generic Low-class apartment."

Hell, I think only 1 of my 5 players has an apartment. One has a Town-house in a middle class area, one has a warehouse in a lower class industrial district (though it is very nice inside), another has a section in an old sewer, and the last one slips my mind at the moment.

*edit*
He has some sleeping quarters in the back of his Shop.

It helps flesh out the character's life. it makes them more than just numbers on paper to think about how she lives etc rather than just "med life style, 5K "

We also use them, but with a few tweaks for making our own stuff.

Out of curiosity, what canon RAW are there for mechanical effects of having a given lifestyle?

It's entirely optional in most cases in my game. The only exception is if a player wants to buy a permanent life style, then we sit down and determine everything that goes along with it. Personally I like the flavor that it adds and wished all of my players did it.

I am using it with my lot, it adds some depth to their lives. The mentalist elf gunslinger likes to keep his apartment at a balmy onehundred degrees and looking like a sunny tropical beach. He lives in the barrens.

As a GM I don't require it, but I did add incentives to using them. We have a game based in LA, and if a player had a squatter lifestyle they began to suffer from exposure (radioactive water? Ewww!), etc. With the advanced option we now have a paranoid technomancer (we're running through emergence right now, with side runs for fun when I think of new idea) in a highly secure loft while the mage has created a magical lodge in an upscale part of Fun City. The other characters have similar fairly unique digs, and the rigger has gone so far as to create a map of his garage in AutoCAD. They really got a kick out of the options and as long as their food and housing is above squatter they avoid (most) of the penalties I had put in place for living on the street.