The price per share is meaningless and arbitrary. If you spend the same amount on either, you’ll end up invested in about the same amount of the underlying 500 companies.
Normally the main thing that would seperate 2 ETFs tracking the same index would be their OFC, but they both have the same OFC of 0.07%. So you might expect their performance to be identical.
But one more thing separates index ETFs: tracking error, or how closely they manage to track the performance of their index. I don’t have a good source that gives a figure for this; does anyone else?
But comparing their annualised performance over ytd, 3 and 5 years via Morningstar, VUSA seems to be slightly better than IUSA, suggesting consistently lower tracking error.
IUSA vs VUSA