The construction of revetted bunkers is a slow process, and with the Eco Bunker it's even slower, because there are 3x as many layers of material to install. The up side is that once you've finished, it should last for a decade or more, and that's a significant budget savings for a club like Pennard. [They told me that they haven't had much $ left over to do any other "projects" in recent years because all the spare income for the year was spent rebuilding the bunkers.]
The down side of the Eco Bunker is that the slow pace makes it very expensive to bring in an experienced crew to do the work. There aren't many architects or shapers who have much experience with building these bunkers. By far the best guys for the work are the crew members who have been rebuilding a % of the bunkers at St. Andrews and Muirfield every winter. At The Renaissance Club, we had a great crew made up of guys from the other local clubs ... but we couldn't be around to supervise them, and sometimes we didn't leave them the right land form for them to translate into a cool bunker shape, because we are just guessing trying to visualize what they'll do.
As someone who has always tried to bring in my own shapers to make sure the finished product looks just how I want, this is a new and less than perfect process. I believe the quality of the work will continue to improve as the crew gains more experience with the materials ... and as we gain more experience in how to direct them.
In the meantime, I'm sure that Pennard will be happy to take volunteer construction help from anyone who wants to pitch in!