WIY and 2scents – I think you are misunderstanding iced’s question (he/she can correct me if I am wrong). He is not complaining that this vinegar-free horseradish is being sold in the supermarket and that Jews are consequently being nichshal – he is simply getting people’s input on whether HIS minhag would allow him to have this horseradish or not – i.e. if others have the same minhag as he does, do they eat this product? Or, a question even for those without this minhag, do people think that based on the principle of this minhag, which clearly has to do with eating foods that are simanim for a sweet year and refraining from those that are bitter/sour, would HE be allowed to make an exception for this product which is less sour than your standard horseradish?
iced – I don’t know. Good question. You def won’t go to gehinom, either way, and I doubt G-d will condemn you to a bitter year for having horseradish, but it is your family minhag, which certainly has some weight. Try your local orthodox rabbi?