I have to second the nomination for Catch 22 bus. One experience I had with them was hilarious for an enthusiast, horrific for a passenger.

It was their first go at the X70 Manchester - Blackpool operated with ex London bendi Citaros. We left Manchester about 30 mins late, I was the only passenger on board though the driver, Wendy, was lovely. All okay, if rather slow, until we got onto the M55 toward Blackpool. Wendy leaves the motorway onto an exit which goes straight onto a roundabout formed by bridges over the M55 below. Pulls the huge bus, two (or 6) wheels on the kerb on the bridge and explains to me as she's so late  a shuttle is going to meet us to take me to Blackpool and she'll go back to Manchester to get back on schedule. 

The shuttle was only one of their Routemasters bombing up the Motorway! Laden itself with passengers to change onto the Citaro to go to Manchester. A very awkward and dangerous passenger swap ensues and we continue to Blackpool, I was sat on the bottom deck and in awe of the open step just meters away as we reached 50mph. 

The return journey was the same Citaro and same driver which gave me a passing thought round working/driving hours as she must have been on the road for at least 11 hours now and looking at the timetable I couldn't work out where she could have had a decent break. Grand total of 3 passengers to go back. Before we left Blackpool we call at the Esso Garage by the coach park to fill up on diesel despite being in service which takes a good 15 minutes. Somewhere along the East Lancs Road the bus slows to a crawl and the rear saloon starts to fill with smoke. In typical Citaro style it's overheated and is knackered! Wendy tries her best but it's no use. 

Being an absolute hero her priority was trying to call a taxi to take the passengers into Manchester, alas no-one will pick us up at the side of the East Lancs in fading light. Soon someone from Classic Bus management (as was the company name then) arrives to confirm the bus is indeed knackered and then to most surprising and technically illegal thing happens. 

We all get in his Ford Focus and Wendy drives us into town in that instead! 

I doubt I'll have a more bizarre bus travel experience again.