Scrubbed through my archives and I have good news and bad news. The good news is that most Smoking Sweeties and Random Snaps videos are so well lit that you can pick up residual smoke from almost all of the models unless the camera angle prevents it. The bad news is that I wasn't able to find many exceptional residual exhalers, at least not the four stream woman you mentioned.There were no Smoking Sweeties models in my collection who made a habit of multiple residual exhales. Although Fran's models can flat-out inhale smoke with the best of them, most are lung emptiers. That said there were two models who stood out other than the ones I mentioned in my last posts.
I can't believe that I forgot about Jessica. She is another smoke holder. She doesn't get much love from Smoking Sweeties fans but she is definitely one of my favorites. She is English (love that accent), looks like she could work in your office, inhales very deeply, and holds it long. She is in two videos with Vanessa who is a Smoking Sweeties favorite, so you get a two-for-one deal if you decide to go that route.
Another interesting case is Bojana. She has an Eastern European look that may or may not appeal to you but she inhales the smoke so deeply that there is a delay when she exhales. In other words, smoke doesn't start coming out until a second or so after she begins to exhale. That is a sure sign that the smoke is deep down in there.
If residual exhales is what you seek then Randoms Snaps is the better bet but not by a whole lot. I've purchased just about every RS volume since Vol 8 and the only residual exhaler that jumps out is Jasmine. Unfortunately most of her better clips are not her own. She appears in some earlier volumes as a guest in other model's clips. I did not make a note of what volumes these clips are from and I suspect that some of them are archived and no longer available. Jasmine is featured in Vol 28, and while she is good (great attitude) those clips are not her best work.
Another good residual girl is Annie. She is an RS staple and has appeared in a bunch of volumes. I'm not big on Asian chicks but Annie is too strong of a smoker to ignore. She has great residuals and she is also a big re-inhaler which I like. She'll take a drag, exhale half, re-inhale, take another drag, exhale a little more, and so on.
The models below aren't necessarily residual exhalers but if you are looking to spend money at RS these are some of my favorites and the volumes they appear in,
Kelley - Vol 29 - This girl is probably the best smoking model I've seen in several years. I could write pages about her but the best description came from the RS message board where someone referred to her as a "weapons grade superstar". Amen. Bonus because Annie also appears in Vol 29.
Amanda - Vol 25 - Love her look, her relaxed attitude, and the way she puts away the smoke.
Claire - Vol 14B - Decent smoker but in my opinion one of the most beautiful smoking fetish models ever filmed.
Bridgette - Also in 14B - Another RS staple. She is good but I really started to like her after Tony wrote on his message board that she is the heaviest and most dedicated IRL smoker he films. That's gotta be worth something.
Katie - Vol 15 - Again not big on Asian chicks but this one is awesome. Best I've every seen and that includes the legendary Kim from Colight. She is so tiny you wonder where she puts all of the smoke she inhales. Also love the way she drags, hungry but not rushed or desperate. There is a clip of her and Annie in geisha clothes that is crazy hot. Stay away from her clips in later volumes. Not nearly is good.
Georgia - Vol 24 - Same overall description of Amanda but with just a touch of bitchy-hotness.
Hope this helps with your decision.
