A bard need not prepare his spells in advance. He can cast any spell he knows at any time, assuming he has not yet used up his allotment of spells per day for the spell's level.
So, with the Heighten Spell (Metamagic) feat, I can use up any of my Bard spell slots to cast Charm Person at any time.
There is no need for Preferred Spell feat to cast a chosen spell spontaneously because I can already do that by being a Bard and having Heighten Spell. Also, Sorcerers, Inquisitors, Oracles, and Summoners can do this as well because they do not have to choose their daily spell alotments ahead of time.
So the Preferred Spell feat would only be used by casters who have to prepare spells ahead of time and want to be able to spam a particular spell at any time.
Correct?
You have to have the Heighten Spell (Metamagic) feat in order to use a higher level spell slot to cast a lower level one right?
You can already cast lower-level spells in higher spell slots whether you have Heighten Spell or not. It's just that without Heighten Spell, a Charm Person in a fifth-level slot is still treated as a first-level spell (DC 11+char, blocked by Lesser Globe of Invulnerability, etc).
The only benefit that Preferred Spell grants to a spontaneous caster is the ability to apply Metamagic without increasing the casting time (such as from a standard action to a full-round action).
You can already cast lower-level spells in higher spell slots whether you have Heighten Spell or not.
I can't find the rule in the Core Rule Book regarding this.
Core Rulebook, page 218
Spell Slots: The various character class tables show
how many spells of each level a character can cast per day.
These openings for daily spells are called spell slots. A
spellcaster always has the option to fill a higher-level spell
slot with a lower-level spell. A spellcaster who lacks a high
enough ability score to cast spells that would otherwise be
his due still gets the slots but must fill them with spells of
lower levels.
Senario:
A 10th level Bard casting Charm Person (Casting Time 1 standard action) in a 4th level spell slot adding onto it the Heighten Spell (Metamagic) feat, Still Spell (Metamagic) feat and Persistent Spell (Metamagic) feat.
The casting time would be 1 round due to adding metamagic feats? Or longer due to adding 3 metamagic feats onto the spell?
A persistent spell uses up a spell slot two levels higher than the spell's actual level.
A stilled spell uses up a spell slot one level higher than the spell's actual level.
So the DC of the spell is as a 4th level spell and I can use these metamagic feats as in the scenario?
So, only casters who instanly get to choose spells as they cast them are affected by increased casting times from metamagic feats right? Druids and casters that have to choose spells with metamagic feats ahead of time dont have that casting time penalty right?
It becomes a full-round action. The DC of it is as a 1st level spell. The only metamagic feat that "adds to the DC" is Heighten, but the levels it adds can't overlap with levels other metamagic feats add.
You can't use Heighten Spell in this scenario, since your max spell level is 4. The base spell level is 1. You add two from persistent to get 3. Then you add one more for Still Spell, for a total of 4.
So, only casters who instanly get to choose spells as they cast them are affected by increased casting times from metamagic feats right?
Yes.
Druids and casters that have to choose spells with metamagic feats ahead of time dont have that casting time penalty right?
Yes as well.
DO NOTE that if you're a druid and you Spontaneously Convert a spell to be Summon Nature's Ally, and you wish to apply metamagic to that spontaneously converted spell, then that spell *will* have a longer casting time.
It becomes a full-round action. The DC of it is as a 1st level spell. The only metamagic feat that "adds to the DC" is Heighten, but the levels it adds can't overlap with levels other metamagic feats add.
You can't use Heighten Spell in this scenario, since your max spell level is 4. The base spell level is 1. You add two from persistent to get 3. Then you add one more for Still Spell, for a total of 4.
So no matter how many additional metamagic feats that you add onto a spell, the casting time is only advanced by one fraction?
I thought that I read that you can apply the Heighten Spell (Metamagic) feat to the spell 1st, making it a level 4 spell DC, which, afterwards then can apply the other spell slot increases from the metamagic feats which have already been taken into account by the Heighten Spell (Metamagic)feat?
What about if I had Preferred Spell (Metamagic) feat? Would the 1st level spell still not get the 4th level DC when adding the other Still Spell (Metamagic) feat and Persistent Spell (Metamagic) feat?
Yep, no matter how many metamagic feats you apply, it's just a full round action. Assuming it was normally a standard.
Your second point is a somewhat common houserule for casters who prepare spells. But it's not in the rules.
I'm not sure about the feat.
You cannot spend slots you do not have. If you have no 4th level slots, you cannot cast an Extended Haste.
The exception to this is if you have some way to ignore the increase in slot level, for example through the Magical Lineage trait or through using a Metamagic Rod.
Note, however, that if you cannot cast 4th level spells for some reason but still have 4th level slots (for example, if you're a 10th level bard with a Charisma of 13) you CAN use these slots to cast an Extended Haste (because it uses a higher slot but does not have a higher spell level).