I stayed here as a resident of Japan for over two months after living elsewhere nearby in Itabashi for a couple years, so I have a bit of local knowledge of the area.
The location is very convenient - you're less than 5 mins walk from the Mita line, and a couple other major lines are within 15 mins walk also (which lead towards central Tokyo and also north into Saitama, Gunma etc.). Lots of options for shopping, restaurants, convenience stores, drink vending machines etc. You won't be left hungry or thirsty, even at 3am.
As for the place itself, it's small and cosy and has all you need for day to day living - fine for either a single person or a couple/small family. As mentioned, I stayed here more as a resident than a traveller and I could happily have stayed longer-term and would be comfortable enough. Many daily utensils and goods are provided - cutlery, plates/bowls, seasonings, oil, garbage bags, cleaning goods, toilet paper etc. etc.
If there are any negatives - the place is cold and dark in winter with only one small window that faces the direction of sunlight, a window which is semi-blocked by the house next door, and whatever sun there is disappears by late morning. Therefore, it feels somewhat like a basement/internal granny flat of sorts that has been converted into accomodation (it's kind if part of the larger apartment above from it), but the heater in the bedroom does warm the place up after a while - but none of this matters if you're out and about exploring all day on your holiday. Also it's a bit noisy after midnight as there is a newspaper delivery centre literally outside ther bedroom window, and people come and go throughout the early hours, but it's not a major disturbance. Controlling the heat of cooking is a challenge with the little induction cooker stove also, but the typical traveller probably eats out more than I did. It would also be nice if the closet in the bedroom was available to be used for storage, instead of being locked off with a bike lock - but again that's probably not an issue for traveller with only a bag or two (I had boxes and boxes full of possessions). Nothing here on the negative side was a deal-breaker though, not at all.
The best thing is the communication with whoever it is that replies to messages (your contact isn't the owner directly) - very fast replies, and I had to make quite a few changes to my dates, and also had a couple special requests, and they were very flexible and accomodating to my needs.
Overall, I strongly recommended this place and location, and it's worth mentioning too that Itabashi in general is one of the better areas of Tokyo if you want a surburban yet still somewhat urban Tokyo feel without the crowds and madness of the touristy areas - in fact it's my favourite part of Tokyo. Come and stay here and check it out.