most/least successful

Non-PRO English to French Bus/Financial Business/Commerce (general)

"Now please select which of these ideas you would double your shares in (i.e. you think would be the most successful in the market.
Please select which one of these ideas you would immediately sell your shares in (i.e. you think it would be least successful in the market)."

Parle-t-on ici de bonne ou mauvaise performance d'un concept, et si c'est le cas, je le mets au singulier ou au pluriel?
....si vous pensez qu’il aurait les meilleures performances sur le marché
... si vous pensez que le concept aurait une meilleure performance sur le marché..

Merci :)