Hi merelyok,
Yup you in SG too? I use the same handle/nick in the local forums (echoloft/Xtremeplace). : ) I guess you'll be getting the same stuff from the same dealer?
Cables....Nothing special, just van den hul CS-122 single run (well the Adagio can't be biwired, so i save here...ha!) and DHLabs Air Matrix w/Eichmann plugs, both silver coated Long Grain copper.
Do change the input bypass and coupling caps in the 318Bn,
you will find that the amp leaps into another league.
Whether or not is it just an improvement or difference depends on your tastes. The Adagio is not exactly very sensitive at 89dB/m/w so for tubes try to go for at least double digit wattage tube amps, esp if your music demands the headroom. The Almarro can be made to match the Adagio and your tastes sonically just by changing the caps, which won't cost much.
Let me know if you have any questions in echoloft, i have a thread on the 318B there.