Not the same but similar. Intergerrima fruit has more sugar content:
http://jurnal.ugm.ac.id/jfps/article/view/1846
It seems any plant with too many positive attributes over those around it is invasive. I have autumn olive which is invasive. I planted several along a fence a couple years ago and I'm very happy with it.
Berberis Darwinii is considered invasive, but I'm not sure why after reading the following info found here:
http://www.issg.org/database/species/ecology.asp?si=1622&fr=1&sts=&lang=EN
Berberis darwinii exists as varying habits in New Zealand from shrubs with interlaced branches, reaching 3-4m in height and 3-6m wide in the open and at the forest edge to lianoid small trees growing to about 10m and spreading 15m under the forest canopy. Dispersal is key to B. darwinii's survival. Introduced bird species act as dispersers in New Zealand. Despite being considered a shade-tolerant species it has been shown that B. darwinii actually requires high light environments to germinate. It is tolerant of both frost and drought.Description
Berberis darwinii exists as varying habits in New Zealand, from shrubs with interlaced branches, reaching 3-4m in height and 3-6m wide in the open and at the forest edge to lianoid small trees growing to about 10m and spreading 15m under the forest canopy (Allen & Wilson, 1992). Dispersal is key to Berberis darwinii's survival as shown by MacAlpine & Jesson (2008). They found great numbers of seeds dispersed at least 150m, with others also being consistantly detected up to 450m away from the parent population. This was further shown in their study with seedling survival; nearly all seedlings under the parent population died within the first 5 months of germination. Despite being considered a shade-tolerant species (Webb et al 1988), MacAlpine & Jesson (2008) and MacAlpine et al (2008) have shown that B. darwinii actually requires high light environments to germinate. It is tolerant of both frost and drought (Allen 1991; Timmins & Mackenzie 1995; as seen in MacAlpine & Jesson, 2007)