Australian Dilemma - Great Ocean Road vs Phillip 'Penguin' Island?

For my last day in Melbourne, I have a dilemma between 2 equally exciting options to end my visit on a high.

I have to choose between:

O) Great Ocean Road
P) Philip 'Penguin' Island Parade

Here's why:

O) Great Ocean Road (up to London Bridge only)

• 12 Apostles Limestones stacks
• Loch & Gorge sea cave
• Limestone cliffs
• Kennett River: wild Koalas
• Great Otway National Park: rainforest & waterfall
• Bells Beach

or

P) Philip 'Penguin' Island Parade

• Watch penguins waddle ashore at sunset
• Handle kangaroos & wombats
• See emus, seals and koalas
• View island, bay & rocky outcrops

The cost of both bus tours is AUS$100.

Yes, I know I should hire a car for 3 days and drive around but I don't have the time, energy or willpower :-(

I also expect that with bus tours, they will be long shuttles, briefly interrrupted by 5 min photo shoots & 10 min to rampantly consume the gift shops.

So, which should I pick, O or P and why, please?

It would help me a lot if you would post a comment on my dilemma. I'll you know what I choose and how it turns out.