The bag of farfel is the same no matter where you buy it. Just look for a store that offers the amenities that are important to you. Is it convenience (short commute, offer delivery, everything under one roof, easy parking), low prices, large selection, multiple departments (fruits, vegetables, take out etc) and shop there.
soliciting advise online can lead to serious halachic issues as you get more responses and they start putting down stores by name.