we run a transit crew cab tipper with a removable chip box.find it incredibly versatile,the chip box has 3x worklights,2xrear beacons and a reverse camera built into it,all this simply unplugs via a 7pin trailer plug from the headboard.removable in seconds which allows us to put the compact tractor/timber/larger items onto the original body.
a chap i know runs 7.5tonne dafs, done a few days for him and i prefer our transit tbh,quite often he cannot get into the smaller domestic jobs with the trucks due to their size weight on driveways etc so you end up lugging crap further thus creating more mess and adding time to the job ,plus his o license,checks,limited drivers due to license etc etc.becomes awkward
we find the transit good in most conditions with the all terrain tyres,if it gets too wet then we revert to the tractor and trailer.
i now hear that the dafs are up for sale as he is downsizing to trannys,due to increased operating costs,and a general downturn in work.
both 7.5 and 3.5 have their pros and cons but if you need the additional capacity,can afford the o license and downtime with checks etc etc then go larger,but if not stick with what you know,more trips but less mither