Out of the box? Not in a million years.
Conceptually, Epic Spellcasting is great. It's based on an entirely different mechanic than 1st-9th-level spells, which allows players to feel like their PCs are doing something *different* and thus makes ES feel different. It's immensely (nigh-infinitely) flexible. It allows for great plot hooks. Because it runs on a different "track" from spellcasting using Improved Metamagic/Improved Spell Capacity, it even allows epic spellcasters a greater degree of specialization: Either they can become mighty machine-gun engines of destruction, or true magical artisans.
The execution, however... leaves something to be desired. Basing it off a skill mechanic means that there will be a *vast* difference in spellcasting ability based on a few simple (effectively costless) skill boost items. Mitigating factors (especially the ones used) mean that casters will figure out umpteen ways to min-max the heck out of the system and cast world-shaking spells at overly low cost. Worst of all, the linear scaling of numerous factors, especially conferred bonuses and durations, coupled with the ability to mitigate by increasing casting time, mean that the most common epic spell will be a long-term buffing application, which, at a mere +100 DC for a +50 enhancement bonus, equates to untouchable ACs and unbeatable spell save DCs.
I've seen fixes that I would *consider* allowing IMC, although I have the feeling that I'd still be invoking the most important Epic Spellcasting rule of all:
SRD said:
Approval: This is the final step, and it’s critically important. The epic spell development work and reasoning must be shown to the GM and receive his or her approval. If the GM doesn’t approve, then the epic spell cannot be developed. However, the GM should explain why the epic spell wasn’t approved and possibly offer suggestions on how to create an epic spell that will be acceptable.
This may sound a little outrageous, but to be honest, I think I'd just prefer to use Feanaro's "epic spellcasting DCs convert to spell levels above 9th" system and create a list of spells of those levels, just as there are spell lists for 0th-9th-level spells. Otherwise, I feel like the approach to any really serious dilemma will be "create an epic spell that resolves this" and come down to a resource expenditure issue.