We have a Burstner with a MAM of 3500kg. The chassis has clearly been downrated by Burstner as the Fiat plate in the engine bay says 3650. Last weighbridge visit I did last year I was 60kg under (3440kg). I've done a few changes since then (major one being replacing single 13kg Calor with single 11kg Alugas). So I recon I'm getting fairly close to the max but don't see us adding much more. But there is always that bit of uncertainty about going over! I'm pondering getting the 'van uprated to 3650 or maybe 3850 (I don't suppose there is any reason not to go to 3850). Have others that have up rated found it worthwhile to up rate given the restrictions that it imposes (speed limits, access restrictions, tolls, age - but I have 7 years until I'm 70!). I haven't done a weighing this year but don't expect much different to last. I shall be visiting the weighbridge next time we are out.