IMO its worth a try.
Any food, not just what is classed as 'high end food' could end up being the one that suits your dog best

If the one s/he's on isn't working then there are a lot of dry complete foods out there that are 'easy on the digestive system' which you could try including James Wellbeloved, Burns, Arden Grange, Wafcol, Chappie . You will need to try the food for about 3 months to see whether or not it will suit your dog fully :)