Ah so you are flying in Delta One JFK-LHR?
In that case yes you will be able to get into the Clubhouse at JFK, no status needed.
As far as thoughts go - there are no trip reports on the forum of Delta's A330 business product. You might have to dig around online for some. But from what I've seen it looks like a good product. There are a handful of reports about the older 767 product, and although the seat may not be the same there will be descriptions of the service:
viewtopic.php?f=21&t=296646viewtopic.php?f=21&t=296151