I've been told dwarf burms tend to be more flighty and high strung than full size burms. Kind of like the same thing I hear about SD retics.
And I also have heard the same. But with more in depth research - I have found this mostly applies to WC dwarfs or early generations(F1-F3) of captive bred dwarf brums. In addition this may depend on how the owner cares for them. As I also heard of captive bred dwarf brums which are being described as "tame" and handleable.

In terms of size for dwarf brums (progschai) - pure(100 %) dwarf brums tend to range - between 4-6.5 feet on average. An exceptionally large female may be up to 8 feet long. Most pure dwarf males are about 4-5 feet. While the pure dwarf females tend to be about 5-6.5 feet. At 7 feet a pure dwarf brum is considered to be above normal in size. By comparison - the Half Dwarf(50%) brums are larger - with males averaging 5-6 feet in length, Females typically averaging about 7-8 feet. Half dwarfs are known to reach 9-10 feet in length.