(26 May 2021, 8:42 am)streetdeckfan wrote Legitimate question here, why does everybody seem to be obsessed with getting heavier duty vehicles (like the E400MMC and 6 cylinder StreetDeck) for routes that a lighter duty vehicle (like the 4 cylinder StreetDeck) would be more than adequate for?

Just because a route is currently run with B9s, it doesn't mean it needs to be replaced with a vehicle of equivalent power.
Take the 10s for instance, now granted I haven't used them for a while for obvious reasons, but I don't think there is a part of the route that a 4 Cylinder StreetDeck would struggle (I may be wrong on that though)
From my experience the StreetDecks used on the X1 seem to be perfectly fine.
And I think we can all agree that the B9s on the Cobalts are beyond overkill!

I largely agree, especially that the B9s on the Cobalts are overkill, but I think time will tell for the X1. It seems to be coping ok at present when I've used them, but the section between Gateshead and Wrekenton is a killer. 

(26 May 2021, 9:30 am)Andreos1 wrote I used the X20 yesterday. First time since the vehicles were upgraded from Solo.

Versus the Streetlites on it prior and the Solos which haven't long been displaced, the 11 year old Merc was a much nicer experience.
Obviously it's the heavier of the 3, but the ride quality was better and the rattles fewer.

Some people may be obsessed with engine power or torque and it may be that a lower spec engine is suitable for that route.
However build quality and the structure of the vehicle is just as important if not more important - from a passenger perspective.

A Streetlite may be powerful enough to work the Durham - Stanley route and it may save the operator a few quid in fuel costs. But is the on-board experience and ride quality worse or better than when the Mercs ran it?

I used them the other week, and completely agree in terms of Citaros. Even though I think the quality of the refurbishment they received a couple of years ago is starting to show.

Of course your average customer simply doesn't care about the mechanics behind a bus. Only that the bus gets them from A to B and that it is as enjoyable of a journey as possible. The Streetlite isn't a good passenger experience for me; you feel every bump, hear every rattle and only a small child would find themselves with enough leg room. The E200MMCs on the 97 are streets ahead of the Streetlite, and I think it's pretty much the same bus underneath!