I have used S04 for most of my recent ciders and find that it ferments quite reliably. About 1-2 weeks primary until the turbulent fermentation settles, then rack to secondary for as long as you like. This year I also did some with M02 (Mangrove Jack) because of its reputation for leaving some sweetness and have a small comparison batch (same apples/different yeasts) but haven't done the taste test yet.
I also find that leaving the cider for 6 -12 months results in some sweetness, or at least less harshness, probably because any harsh acids mature over time and have less dominance (but I really don't know if this is the reason).
Just to confuse things, AS-2 (which I hadn't heard of) from Fermentis/Safcider was mentioned in another post about a week ago. A bit of research turned up a paper by Etienne Dorignac - Technical Manager, Fruit Fermentation at Fermentis. The French/English translation seems to stumble a bit and some of it is a bit beyond me, but the essence of it is that they have four "new" cider yeasts AB-1 (Apple Balanced), AS-2 (Apple Sweet), AC-4 (Apple Crisp), and TF-6 (TutiFruiti).
Following is an extract from their taste tests...
"Finally, a simple evaluation of the basic tastes was done: Sweet, acid, bitter and astringent
From these tastings, SafCider™ TF-6 (especially) and SafCider™ AS-2 were scored as the highest in fresh but also cooked fruits, whereas SafCider™ AC-4 was judged less expressive and predominantly oriented towards freshness; and SafCider™ AB-1 was more discrete (data not shown).
More interesting were the detailed fresh fruits perceived by tasters as shown in Figure 4. Obviously, sensory characterization of all ciders was driven by detection of apple notes, but SafCider™ TF-6 scored high for most of the fruits, especially banana-pear and red fruits. SafCider™ AS-2 and SafCider™ AC-4 respectively exhibited more citrus and floral notes, whereas SafCider™ AB-1 was mainly centered on apple".
What does all this mean?.... Don't know, but I will try AB-1 or AS-2 next year (our cider making season is over).
On balance apart from these "new kids on the block", S04 would be a good starting point as it is well known and sometimes finishes above completely dry (i.e. 1.002 - 1.004) which leaves a touch of sweetness.
If anyone else tries these new yeasts, please post. I am intrigued.