I used silvermere and thought they were good. Prevision golf is next level, both in terms of what they offer and their pricing as they typically use after market shafts rather than the standard stock shafts manufacturers offer.
If you want a proper fitting then Precision Golf if where you want to head. They're only up the road from Silvermere and to be honest would rate them far higher. That said their fitting isn't the cheapest so that might be an issue but they are the best fitters IMO.