I bet the Bristol 35 will go faster than 6.35 K. Long overhangs that boats like that have make the sailing length longer than the waterline.
There must be some application for the Bristol line but I don''t like any of the smaller ones that I have seen.
My boat is old too but for coastal crusing it just has to be a better sailor than the Bristol 35.
The catalog that I have shows the C&C 35-1 and the Bristol 35 next to each other. The C&C has a IOR MK 111 rating of 29.0'' There is no rating for the Bristol!
In light air the Bristol 35 will be a dog. Install a 275 gallon tank or keep looking.