From the outside, this place doesn't look like much - but step inside and you are in for a treat. There are much flashier (and more expensive) Japanese restaurants out there - but Asakusa focuses on serving authentic, good quality and competitively priced food.
Having recently eaten at the trendy (but, unfortunately named) Tsunami in Clapham North it brought home to me just how good Asakusa is. Tsunami's signature sushi, the volcano roll, looks impressive on the plate - but in the mouth it is just a california roll drenched (and I do mean drenched) in mayonnaise. No such frippery here - just outstanding, traditional sushi.
The only downside to the restaurant is the slightly odd opening hours - so check before you go.