Vince,
I'd like to purchase some copies of the XPRESS LP solver for the gas storage 
optimization model.  We have previously discussed the purchase of CPLEX, but 
after trialing both systems, have found some worthwhile advantages with 
XPRESS.  If others find Planner / CPLEX best suited to their application, I 
see no problem is their use of a different system - both have strengths, and 
it is likely that I would use Planner/CPLEX myself on some future project if 
we were to have both systems available.

XPRESS is particularly suited to my application because it handles Special 
Ordered Sets.  This is a very efficient way of representing the storage 
ratchets as the integer search process is able to use the extra information 
provided by the set, rather than just using binary integer variables to 
represent the ratchets.

Planner is a C++ interface for CPLEX.  It has some significant limitations, 
and does not permit access to all CPLEX features.

Dash Optimization have made the following offer:
All software purchases made by Enron this year will be at 30% off the list 
price - we do not need to make a single purchase of any specific quantity of 
licenses to obtain this discount.
90 days of full maintenance services will be provided with the purchase.
The EMOSL utility will be provided at no cost.
The XBSL system will be provided at no cost when it is released in a few 
weeks time.

For the Gas Storage Optimization model, I would like to purchase:
One development license, hyper version, with modeller, primal/dual simplex, 
MIP search, dlls, EMOSL and XBSL when available.
 List price $10,000  Discounted price  $7,000
Two run time licenses for above,
 List price total $8,000    Discounted price  $5,600
     Total cost  $12,600

I've used the usually security request system to set the purchase process 
going, should you agree to this.

Tom.