WOD: PreOrder Now

We have over 4000 skus constant flux of inventory and this app is essential to customer service. Works well and dev is very responsive. Great to work with. Takes thought to get most of it but powerful app.
Update, Now 50k skus and app dev helped with css on mobile wouldn't be without it, works really well.
Update2: Change to App now injecting code into cart template and screwing up prices on my theme......almost at the stage of deinstalling it, but support made a mod for my store!!!! Awesome support!!!