Gisburn is an artificial trail centre in a sterile commercial forest so be prepared for parking problems, competitive other riders and slow zig zag progress through the countryside. Oh, and one cafe.
Hebden Bridge is a fascinating Pennine town at the centre of what was for centuries an important wool-producing area. Packhorses carried the goods from settlement to town and back so that part of the Pennines has a massive number of old packhorse trails, bridleways, tracks, tramways and towpaths, which you can follow all day by using a map. The landscape is stunning because HB sits in the bottom of a deep gorge, which has heavily wooded sides below glacier-sculpted open fells. There are plenty of cafes and pubs and fascinating shops. The natural landscape is complemented by some amazing Pennine mill architecture. Does this sound like a tourist brochure? Anyway there's no contest, it's Hebden Bridge every time.
(PS: Not for nothing does Singletrack magazine have its office just down the road in Todmorden)