Is a vitamin C complex better than plain vitamin C?
Only if you want the other ingredient. For vitamin C alone, plain ascorbic acid is cheaper and does the same job.
What is rosehip doing in it?
Rosehip is a traditional food source of vitamin C and is used as the base in Biocare's complex.
Should I split the dose?
Generally yes – vitamin C is water soluble and not stored, so spreading it across the day is more useful than one large amount.
Powder or tablets?
Powder lets you vary the amount; tablets are simpler and more consistent.