Great place and location! Just down the road from Clapham Junction and only £6 return on train to Waterloo which takes you right next to center of London. Pub itself is lovely, but does get busy on a night time due to its popularity! The food is delicious and you get a discount for staying in the hostel. Check in and security is top class and very easy.
Only negative was that it was very very hot in the rooms at night. There needs to be a fan or some way to circulate the air as it was uncomfortable to sleep. But, overall highly recommend!