On relection, (with the benefit of a proper keyboard at home), the day was quite interesting. As I boarded at East Croydon, travelled to Bedford, then back to Blackfriars, I had experience of ac & DC slow running in the core and moderate (well crawling actually) through Tulse Hill and Herne Hill with a lively performance north from West Hampstead. Acceleration on ac is quite stunning, reaching 98 before St Albans. Stability seemed fine even over the rough down line from Crcklewood to Mill Hill where even new 387s go all over the place.
Only heard one criticism from a passenger, getting on at St Albans on the up journey there were comments about the lack of tables. Heigh Ho, - maybe they will be on a packed train in the core at peak times soon.