The retinoid is real retinol, not an ester and not a blend of things that are not retinoids. The "Complex" in the name refers to the antioxidant system the retinol is encapsulated in — not to the retinoid being padded out.
That is a meaningful distinction, and it puts SkinMedica well ahead of the products here whose "complex" hides a weak ester or an algae.
Airless pump, which is the best packaging available for retinol.
No added fragrance, and the supporting formula — niacinamide, peptides, ceramide, vitamin E — is genuinely well built.
Irritation is expected, not a sign it is "working." Redness, flaking and stinging in the first weeks are common with any real retinoid. Start twice a week and build up. If it is still angry after a few weeks, the dose is too high for you.