Even fast acft need a lot of forward trim at high speed. A real-world example, P-51 based to boot: Reno racing Mustangs require full forward trim and then some stick force to maintain level at their top speed. When the elevator trim assembly failed on Galloping Ghost in 2011 the aircraft pitched up at 17.3g, blacking out the pilot and the acft crashed into the crowd. An earlier similar incident the pilot escaped - fortunately it pitched straight up at only 10g instead of rolling
Sorry (with deep respect for the Reno Pilots) ..... but a model racer can be set-up to be neutral at WOT - I know from my own model racing.
A model can be altered so easily by spacer under wing mount .... cut and reglue tail .... washers in motor mount ... with no requirement to pass an Aeronautical Official Inspection ....
My RM Racer was reasonably successful and was zero trim at WOT ... I'd LOVE to have that bird again ... but passed it to another guy when I left UK.