convenient, nice
The Internet policy was pretty bad: you purchase, e.g., a 2 hour coupon, and if you shutdown your PC without accessing 1.1.1.1/info to logout, the clock will continue to tick, and you'll use up your service. Then if you realize it after you left your room, the lobby will not help you by stopping the clock for you. Two nights (of 7) the net connection was inaccessible - couldn't even access 1.1.1.1 - but fortunately I was not yet logged on at the time.
Elevator was very strange - can't exit directly to the street without going through the lobby. But this is done for security, so it's reasonable.
On the positive side the staff was helpful and friendly, and the rooms were really large, and clean (but I had a view of only disused buildings, pretty depressing). Farther from the station were some hotels with better value: people at my conference were happy with the Hilton, Ibis, and Residence, all for lower than Hyllit (I paid EUR105-130 per night).
Breakfast is nice but at EUR17, I recommend trying one of the many many closeby restaurants or bread shops. The room had a small refrigerator, so I recommend you take out all the wines and drinks, put them in the drawer, and for breakfast you could stock the refrigerator with Belgian cheeses and breads and chocolates bought at the grocery store underneath the large movie theater across the street, named something like Mart or March or something like that. Underneath the Wagamama noodle restaurant.
The pool and sauna in the basement were nice and uncrowded but small.