It's a good site, I've used it since early 2015 so I could access my required units list while I'm out and about. I haven't upgraded my membership to access the record your haulage listing just yet, so for the time being I'm using the "record your sightings" list for this purpose. I'll probably upgrade when I start going out more regularly again to make the post of the extra features.
It does remove scrapped units, for example 507022 and the scrapped Class 508s aren't included on their respective class lists, although the surviving 508 cars are still listed (for now anyway).