We took the 9am bus from Batumi railway station. Cost 40 Gel.

In hindsight we should have got out of bed a little earlier and taken the 8.10am train instead.
Train tickets were 100 Gel and the journey only 5 hours with toilets.

The problem with the bus was that there was a single rest stop halfway through a 7 hour journey.
It was a very nice stop with clean toilets (1 Gel coin to enter) and a restaurant with some tasty food.
The problem was it was the only stop !!

There were some nice distant views of ice capped mountains and the bus driver was very careful and professional (apart from his chain smoking that wafted down the bus).