Hello,
I'm searching for a site file with more 1000 points.
18,000 points is it a current size ?
I do a parallel version of s.surf.tps and I have to test it on some
site files. The biggest one I have for this moment is bugsites with
80 points that isn't enough. 
You could send me a mail to see I could take it.
Bye,
Stephane VERNAT
My mail : svernat@ens-lyon.fr