The 294 arm is a 12 inch arm and i think it has a higher mass compared to a shorter Spacearm. So I think you can not just ask how does a Grado works on a Nottingham because someone might say its great, but with a Spacearm.
I'd think the 294 would be better suited to a MC cartridge. I'm assuming the Reference Grado is a typical MM higher compliance cartridge. I won't bother checking because I am far to lazy to bother trying to figure out Grado's stoopid model names.