Wow talk about under promising and over delivering. My trees arrived today (4x acer freemanii), I'd ordered 3.5 - 4.5m tall and the shortest was 5.5m and the biggest 6.2m

They're along the front, higher than the phone line and level with the power lines. Oops. I'm nervous about winter gales but I've got big double stakes and (I'm told) you keep the supporting 2" bamboo poles in for the first year so fingers crossed.
There comes a time you realise you're too old to buy small trees which is a bit of a chilling reality check.
The supplier was ornamentaltrees. Highly recommended and they keep in touch by phone rather than mail which is a nice touch.
They must have sent the wrong ones, I checked and mine should be in 35l bags and these were 65l. Too late now though they're in.