I know the question was regarding Independents but I'd recommend Carrs in Exeter, the main dealer. They looked after my 355 for 7 years and now my Spyder.
The Service Manager is Steve Ware and the service has been excellent and will collect and deliver the car if required. They are also happy to fit non OEM parts (eg Hill Engineering) if requested even emailing me a photographic record of work done and despite looking at Independents, they always match the price.
Not used F Tech but heard good things and intend to pop in at some point for a chat.