Stayed here over the weekend. Was definitely rather disappointed by the stay.
On check-in I got recognition of my Platinum status and one of the "You're upgraded" covers for my keycard. Despite the hotel appearing relatively empty, my room was either the base category or a Deluxe, the next one up. There was no view and being right next to the elevator we heard beeping and conversations every time someone entered or left the floor. Overall the walls appeared oddly thin for such an old building - We did have people in the room next to us at one stage and we could hear the cutlery move as they ate.
The automated system allowed high speed Internet access for 24 hours twice (i.e. one device is one period). We also got a couple of vouchers for low speed access. I had two phones and a laptop and my guest had a phone so we just about made do by only having our devices on for some of the time, but that felt pretty bad.
They have a cross-keys concierge who seemed quite up to speed and was able to arrange some services for us. We popped by after dinner one evening on our way to a bar and asked one of the other concierges to send an ice bucket up to our room and we were told that we had to go up to the room and call room service from there. I thought that was a pretty poor effort from a 5* hotel.
Room cleaning also felt a little low effort. We received quite a nice welcome Platinum eclair on Friday but policy is apparently not to take it away until it's done - so we still had half a smelly and slightly moldy eclair in our room when we left on Friday afternoon. Similarly items in the bathroom aren't rearranged, clothes and left lying around, etc.
Overall, I didn't find this place up to the base 4* Meridien standard and certainly not up for a 5* period building prestige hotel that it's positioned at in the Hungarian market. Thanks to some fiddling I got rates of around €130EUR a night, but I've often seen it at €180 which I really can't see how they could justify.
The Four Seasons is clearly more expensive, but looks great. Next time in Budapest I'd consider the Corinthia or possibly one of the other chain hotels (Kempinski, Intercotinental..).