We would recommend using the same timber as the floor if you can. This would make sense and keep your material palette as simple as possible - there are some fantastic timber finishing treatments available that will provide a durable surface that is easy to maintain. There may be a way that you can introduce a separate timber element say 40-60 thick that sits on top of the existing solid top... perhaps a bit like the kitchen in this image by 'Beef Architects'http://www.contemporist.com/2013/06/21/riverpark-apartment-by-beef-architects/ap_210613_07/

Thanks everyone for all your feedback and tips. Below is the plan I have come up with. Not sure how clearly it will show up. Have wrestled with the position of the ovens and sink - thought about swapping them and about having them centred but then think there would be too far between fridge and cooktop/ovens. Cooktop is 600m gas, then two below bench 600mm electric ovens, 900mm rangehood. Sink is double drain, double sink (1550mm in all). I know this seems excessive and against trend but I could not live without my double drain as always defrosting meat, bottles of milk etc and like to have one clean side and one dirty side of the sink. I love the idea of a bi-fold door appliance cupboard for toaster, kettle, microwave but not sure how practical it really is. Will the doors when open be painful and stick out near the fridge???? Do like the idea of having all that stuff tucked away though. What do you think of dishwasher position? Think I will make that gap between island and bench with dishwasher 1300mm as suggested. The only drawers I'm planning on having are a bank of 3 x 3 800mm in the island. I know that are more economical space wise but trying to keep costs down. Should add that behind the L-shaped benches will be windows as much as possible. Looking forward to your feedback. Thanks greatly.

The volume builder's offer it cheap (or standard inclusion) because they bargain down the supplier and installer who will be suppling many (i.e.: volume) bench tops of pretty much the same size and specification..... Custom designed/bespoke/renovation dwelling's cost so much more because they're 'one off' rather than the same design being built many times over.

I've long been concerned about the formaldehyde in laminates, which also continues to outgas after installation, but until recently questions about it were met with a blank stare. A few years ago I was pleased to see a sign in the kitchen section of Masters making a claim regarding that (I think it was the first time I saw the E0 rating?) but when I asked for information about it no-one knew what it meant and eventually they suggested I talk to their 'supplier' which turned out to be the hardware supplier who knew nothing about the laminates. Very disappointing when retailers of better safer products fail to take the opportunity to educate customers and promote those products. Good on you Anne Marie for wanting to ask intelligent questions. (I could start a whole new thread....)