ABS+ is more of a marketing name than an actual type of plastic.

Usually it's things that are added that are actually not even ABS.  For example, Esun ABS+ lists a downside of 'not being as affected by acetone' which means it isn't pure ABS plastic.  Formfutura ABS+ supposedly is stronger, yet warps more so if I had to guess they are some proportion of ABS/PC.

You won't find 'ABS+ pellets' though.  If you bought some ABS/PC pellets off Ebay for example, and you wanted to sell the filament you could conceivable call it 'ABS+ Filament' and brag about how it has improved mechanical performance.

Yes, on properties ABS/PC it is similar to ABS+, but on the website stratasys, they are different materials.And viewing their physical and thermal parameters, I mark rather big difference in characteristics.

Usually it's things that are added that are actually not even ABS.  For example, Esun ABS+ lists a downside of 'not being as affected by acetone' which means it isn't pure ABS plastic.  Formfutura ABS+ supposedly is stronger, yet warps more so if I had to guess they are some proportion of ABS/PC.

You won't find 'ABS+ pellets' though.  If you bought some ABS/PC pellets off Ebay for example, and you wanted to sell the filament you could conceivable call it 'ABS+ Filament' and brag about how it has improved mechanical performance.

UPD:one of developer speaks about some additives and what additives he doesn't want to say