Amber Sarcophagus vs. Forcecage

[Hiro Quester]

The problem with forcecage, is that creatures can teleport out of it. At higher levels, when practically everything can dimension door or teleport, its usefulness is limited (unless combined with Dimensional Anchor).

Enter Amber Sarcophagus (BoED). Like Forcecage it is a 7th level spell. It requires a ranged touch (no save), but allows SR, and has a 500 gp material component. But for a gish sorcerer, it can be greater arcane fusioned with True Casting or Assay Spell Resistance, to help defeat SR.

Amber Sarcophagus traps the target creature I'm a bog blob of amber, for days/level, during which they are held in stasis; that is they can take no actions at all (they are also protected from all attacks, even mental ones, they don't need to breathe or anything, which also has some protective uses).

For a level 21 Sorcerer/Swiftblade/Unseen seer I'm developing, I'm feeling like Amber Sarcophagus is a better option for taking one bad guy totally of a fight.

I see the 500 gp component, but at this level, my character will have enough gold that this isn't a significant issue.

The only other advantage I see for Forcecage, is that it can be cast during a time stop, as a BFC measure, and that it can be cast defensively (http://www.giantitp.com/comics/oots1102.html) to keep the bad guys away..

Am I missing ways in which force cage is better?

[Doctor Awkward]

Amber Sarcophagus always was an obscenely powerful spell, even without needing preparations for specific targets (like ones with high Touch AC's or Spell Resistance).

Do note other limitations, such as its Close range, and the fact that, unlike Forececage, any schmuck with a sizable enough beatstick can walk over and smash it open. It has hardness 5, which is trivial to levels where adamantine weapons are common, and it caps at 200 HP (an ubercharger could probably whomp it open in a single round).

[Deophaun]

It should be noted that amber was once alive, and therefore is a valid subject for unguent of timelessness. 1 day/level just became 1 year/level for practically nothing.

[Kobold Esq]

It should be noted that amber was once alive, and therefore is a valid subject for unguent of timelessness. 1 day/level just became 1 year/level for practically nothing.

No way that works in any game I DM. The amber is a spell effect that explicitly disappears at the end of its duration.

[Deophaun]

No way that works in any game I DM.
i had no idea you were Hiro's DM.