(22 Mar 2015, 7:59 pm)Andreos1 wrote Omni's on the 21?
Marshall Darts on the 194?
Handybus on the 26, 721 and 777?
All replaced, older, bigger vehicles - the first two examples ended up having the originals back on route pretty soon.
The final example ended up with bigger vehicles too.

Granted technology is better now, but the reports relating to loadings won't be faultless.
The new vehicles may even stir additional custom, putting extra demand on the service - like the Mercs did on the X1.

You then have the build quality.
The Renowns have lasted on the 78/8 route since the late 90's, despite some of them looking worse for wear both internally and externally.
A short trial and the word of a sales-rep from Wrights isn't the best way to check suitability.
Council cutbacks may mean the road conditions deteriorate to a worse state than at present.

Like any purchase, it is a calculated gamble.
Only time will tell whether it was the correct one.

I agree with Robert. Go North East is able to monitor how many passengers get on a bus and which tickets/passes have been issued or used for passengers to board using one of its very many systems. This data was used prior to an order being made, and members of Go North East staff were out from early morning runs to late evening runs in August when single deckers (the Euro 6 Mercedes Citaro and "Drifter" branded Streetlite) to monitor and record loadings. This is on top of the extra Saturday bus being provided by a red Versa (when not required to cover for a branded vehicle on the "Citylink" 58 service) from November 2013 onwards.

According to drivers on the X66 service, Go North East does not expect to see market growth as a result of the new vehicles entering service. The new vehicles will see lower running costs (Streetlites are far more fuel-efficient than articulated Mercedes Citaros and there is no increased rate of pay any more) and hence increased profits, so there was no need to revolve a business case around increased patronage.

It's highly unlikely that the Streetlites would last 15 years on the 8/78 services, but I doubt Go North East intend to use them on said services for 15 years anyway... Sadly, I think it's quite likely that most bus operators will look to purchase light-weight vehicles and cascading them to lesser roles quicker than they ordinarily would have done with a heavy-weight vehicle. DaveyBowyer has told us plenty of times about how there is so little on offer for a heavy-weight double decker now, and that's because the majority of the market has been in favour of light-weight double deckers instead so that they can reap the rewards (lower running costs) in doing so. I think it's quite likely that the same will end up happening with single deckers, too.