I think there would be enourmous demand for a ready made 16.5mm bullhead UK outline track - just look at how many club layouts use SMP with copperclad points. I may model 00, but I do consider myself a serious modeller, there is alot more to creating something that looks real than a couple of mm in the gauge - especially when viewing side on. Dare I say it, but there are alot of EM/P4 layouts out there that don't look that real, despite correct gauge (and there are alot of really stunning layouts too). What does matter though, is that flat-bottomed trackwork looks nothing like traditional british bullhead rail and chairs, this to me is far more important than the gauge. Bullhead rail isn't unique to the UK, I've seen versions of it in northern Europe too.
I have the feeling that Peco are rather stuck with their heads in the ground, proof there is that they only just discovered the internet a couple of years ago. The problem is, that unless they move on, somebody else is going to knock something up in China and push them out of any potential market before they even get there. With several European and US producers now producing superior flatbottomed trackwork, they're already slipping behind I magine. Remember, we're only taking about a bit of plastic moulding with rails in, not a new car.
If the cost is a little more, I'm sure that won't be a barrier to those that really want a good product, after all we don't think twice about paying good money for a quality RTR locomotive or stock? Whilst many modellers can't spend the money, there are many that can and will.
The P4 Track Company, SMP & C&L are almost there, it only takes one of them to make that final leap - I'm sure one of them will very soon. Peco, despite behaving much like the stork, will then have missed the boat unless they can then produce something better and cheaper. I think that might well happen, they'll then take the plunge after a third party has proven that there is a real demand.
I predict we'll have ready to lay 'OO' bullhead complete track system within three years.