I booked this place because of how close it was to the O2. You're a stones throw away, so it is super convenient. The views are awesome and you have everything you need for a night, you are also surrounded by places to eat or buy from, so longer stays are easy.
Checking in was fine. I had to pick the keys up, but it wasn't inconvenient. Same with check out, it required dropping them off, but not a deal breaker or anything.