We have 2 days for the above drive - enough time to enjoy it? Thanks.

Yes that would be heaps. I presume you will be driving via the Princes Highway from Adelaide.

Thanks DownUnder - would it be possible to do it in one day as we have 4 nights booked at Apollo Bay and plan to do a lot of day trips from there - so we could just scoot from Adelaide to Apollo Bay but then backtrack a bit for day trips?

You could do it in one go, Elizabeth, but it's a bit of a hike. Depending on which road you take, between 9 1/2 & 11 hours - or longer if you hug the coast road.
It's about 760km (475 miles).

As a rough guide: www.multimap.com

I agree with Bokhara. It is not a fast road i.e. no major motorway sections so it would probably take about ten hours even with short stops at perhaps Mt.Gambier and Pt.Fairy. Depart Adelaide early and you would make Apollo Bay for dinner.
Apollo Bay is a small but lovely place right on the coast. Day trips to the Otways, The Grampians etc. would be ideal.

Thanks all - I think we'll take two days to get to Apollo Bay.....

Elizabeth