Why a 40 hp E-tec, considering that the 60 hp E-tec weighs no more than the 40?
Before buying any inflatable, I'd also confirm what type of fabric is used for the tubeset, and who the actual manufacturer of that fabric is. Generally hypalon will have a much longer life expectancy than PVC (and costs more), but recently there has been some very poor quality hypalon appearing on the market. Orca Pennell pretty much sets the standard for high quality hypalon fabric in different weights. It is better to pay a little more for a high quality hypalon tubeset (thicker is also better, such as the Orca 866) from the get-go, since retubing a RIB can easily account for an additional 50% of the cost of a bare RIB.
Here are the specs on Orca's fabrics - You'll notice that the 1670 dtx weight Orca 866 is much stronger and far more tear resistant than the 1100 dtx weight Orca 828;
Paul Tilley is the fabric/tubeset guru on this board. http://www.tidel.biz/inflatablemanufacturer.php