We booked Appart'City for a 3 night long weekend in July, through Eurostar. At the time we booked, it was one of the cheapest options available. We knew it was a little way out-of-town, in the Madeleine district, but we decided that was an acceptable price to pay to get good quality accommodation at a low price. If you're travelling light, it's easily walkable from Lille Europe, otherwise hop on the red or green tram line (access underground at Lille Europe), and hop off at Romarin - one stop up the line. We found it difficult to actually find the building, and locals couldn't give us directions - it's not obvious that the building is a hotel, even when you're standing in front of it. Appart'City is basically a modern block of apartments which are probably mostly aimed at business travellers, but also available for tourist breaks. So ... you get none of the quaint traditional architecture you might be looking for, but you do get quality fittings, and a fully equipped (in small quantities) kitchenette with fridge & hob facilities. Great if you don't want to spend money eating out & prefer to buy your cheap wine to drink back at base! There's no bar in the building itself, although there's a nice local one about 2mins walk away, which doubles as cafe/restaurant and tabac/newsagent as well as serving draught beers including a dark beer - important for those real ale drinkers who aren't into the usual lagers! We didn't spend much time looking round the Madeleine area, although it does advertise itself as a shopping area. We walked to & from Lille town centre at least once a day, which was absolutely fine. Our only disappointment with the apartment was that it had a sofabed rather than actual beds. The sofabed was very comfortable to sleep in, but certainly in our room, it was one where the second half of the double bed is stored underneath the first half - so when fully in place in bed-mode, we were sleeping parallel to the wall rather than coming out from the wall (hope that makes sense!) It made it difficult for the person sleeping next to the wall to get out in the middle of the night without disturbing the other person. The edges of the sofabed were also very hard (basically a box with the mattresses inside), and very hard on the legs particularly if, like me, you have short legs. I'm 5'2" and I couldn't actually reach the floor to stand up, when sitting comfortably on the bed - I had to squirm around & shuffle myself forwards over the wooden edge (ouch!) to be able to get my weight onto my feet & stand up! When the sofabed is in bed-mode, the room feels small - but it folds up easily and makes a good sofa, and in our room it was well-positioned directly opposite the tv.
Reception has limited hours, but they give you a security code to get into the building out-of-hours. The receptionist who was on duty throughout our weekend was very friendly & helpful, with excellent English.
We would recommend it and may well go back - but if traditional quaint French accommodation, and a town centre location, are essential to you, it won't fit the bill.