I grabbed a £3 copy of Hamburger Hill in Tesco a week or two ago.
Downfall is probably my favourite but there are some great mentions above.
Valkyrie failed to disappoint me in the way I thought it would along with Jarhead (the Iraq bomb disposal one – have I remembered the name right?) but neither up to some of the others above.
Whoever put Zulu up that wouldn’t have occurred to me but good call.
Basically there is no best, far too many good ones to have one favourite.