Yes it is accurate. Equisal will also be at Your Horse Live this weekend so it's an ideal time to pop along and discuss it. Also it will be offered at 20% off as a special.
Vets are simply a bit reticent until peer reviews are published but this will happen soon. It has been well trialed including using post postmortems to verify results.
My own herd have been tested every few weeks since June as we are part of a special study. Very interesting to follow this as one pony had an unexpected high result even though wormed with praziquantel in March this year.
I would not hesitate to recommend the test as all vets soon will too.