What about Griselinia Littorals? Gorgeous, evergreen, very very fast growing and tolerant. I got mine from Trevana Cross in Cornwall and they were excellent and are thriving. You can plant them 1.5m apart and they'll shoot up and fill in super-quick! I planted mine specifically for immediate privacy.
I think buddlija forest is a good idea - getting tall in one season, but not that dense is you are looking for noise solutions. You won't get much of a beech hedge in five years. I wouldn't touch bamboo. A trellis with montana or virginia creeper could cover a six foot trellis fairly easily in a few years.
Just a word of caution. You need to check local by-laws, some areas have restrictions on hedge and fence height near roads. And specifically in front gardens, it would be awful to spend time and money on something that ends up having to be cut down.
Griselinia as mentioned is fast growing and evergreen. Re beech, we have a short hedge of it and it is effectively evergreen for us as it only looses its old leaves as the new ones are appearing. That’s happening just now and although most of the old leaves have fallen, once mature, the twiggy growth is dense enough that you still can’t see much through it and the new leaves will be fully out in a few days.
If you have a garden and a library, you have everything you need.”—Marcus Tullius Cicero East facing, top of a hill clay-loam, cultivated for centuries (7 years by me). Birmingham
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Re beech, we have a short hedge of it and it is effectively evergreen for us as it only looses its old leaves as the new ones are appearing. That’s happening just now and although most of the old leaves have fallen, once mature, the twiggy growth is dense enough that you still can’t see much through it and the new leaves will be fully out in a few days.
East facing, top of a hill clay-loam, cultivated for centuries (7 years by me). Birmingham