Amp vs Crit

There is a lot of debate on what is better. Here is how it breaks down:

These are about equivalent:
 * +5% Amp
 * +10% Crit damage (if you have 25% crit rate)
 * +6% Crit rate (if you have 30% crit damage)
 * +23 Attack

These are also about equivalent:
 * Titanium Katana of Deathblow +6 with +8% crit rate and +20% crit damage
 * Osmium Katana of Deathblow +6 with +3% crit rate and +20% crit damage
 * Redosmium Katana +6 with +20% crit damage
 * Forcium Katana +5 with +10% crit damage
 * Forcium Katana +3 with +7% amp