We had the most amazing experience staying here. Everything we could ask for!! 24/7 reception was a huge advantage. Our apartment (Harlequin) was on the top floor but we did not have issues with the lift as others had mentioned. We made use of the kitchen but purchased our ingredients from the supermarket called Albert dotted all over Prague.
Be wary of Tesco..we found it disgusting!! (Mouldy breads and rude staff). The local corner stores are ok but just corner stores so don't expect to find everything you need.
Anyway, back to the apartment. The artificial fireplace does work unlike previously mentioned. There is first a power switch on top then push buttons to turn on/off. We used all kitchen appliances, dining table, tv, seating and fireplace and bathroom and found everything in order. I'm sure you will too.
To summarise, just book now! You can't go wrong with this place. Don't let the local construction work put you off because it really really isn't a problem.