Gerard,
This is an idea that worked for us up here in Mackay Qld... we were looking for a comfy rider and pillion seat...
Have a look around locally for motor trimmers. We got Coburn Motor Trimmers, here in Mackay, to take off our seat cover, trim off 20mm-30mm of the OEM seat foam and replace it with softer stuff. He then covered again with our seat cover, we rode it down to NSW and back, gave it back to him and got him to adjust the trim a little... and voila... a really comfy, all day long saddle for me and Kate... all for $280... and in his shop for a few days. He also replaced our OEM seat cover with some grippy seat cover material (included in the price). Doesn't mean that your arse gets any less wet when it rains though!
Hope this reply to a different thread, helps. Cheers. John & Kate.