Dwarfs regularly maintain a length of 10 - 12 feet, for females...smaller for males. Super Dwarfs rarely get more than 8 feet, for females...smaller for males.
And, there's no substantial evidence saying they're more flighty or have a higher feed response.
I have regular retics, dwarf and super dwarf. Each snake has it's own personality and demeanor.
The prices for Dwarf and Super Dwarf have considerably declined, as long as you're wanting a normal and not an albino or some other extravagant color morph.