Join Date: Jun 2005
Location: Charlotte, NC, USA | CLT, formerly LHR & AMS (with just a bit of PSP)
Programs: BAEC Gold, Hilton Diamond, BonVoy Titanium, (soon former) Caesars7*, (former) Wynn Black, HR "Icon"
Posts: 8,172
If I couldn't find an award with decent connections (which would mean one connection) from LHR, I wouldn't bother. (actually, I'd prefer a LOW award in Business Class, but I digress).
I track fares to LAS (but ex-AMS), and have found sub 650€ (all-in roundtrip with taxes), but never more than 2-3 months prior.
If I was in London, I would be quite inclined to just take the nonstop (immigration in LAS should be a snap).
Also,
make sure you secure your hotel reservations, as NAB tends to really increase room prices. Most Vegas reservations are refundable (72+ hours prior), but do require a deposit (refundable). Comp rooms, are usually not that much of an issue though; as I helped a relative out with 2 (comp) rooms this past April for NAB.