Which hotel would you recommend?If not any other suggestions. We will be traveling at the end of October

Do you have any conclusions about what you read?

One's a 4 star and the other is a 5 star.

There are significant price diifferences.

If money is no object then I would rent the Presidential Suite at the Mandarin Oriental.

location is the issue not money

We were in Barcelona last month and stayed at Hotel Colon. The location was great and the room was comfortable and quiet. Would stay there again.

Right beside Hotel Colon is the sister hotel, Regencia Colon. Stayed there in a triple - very nice sized and very decent price. Loved the location. Is the Claris more in the Eixemple part of the city? - if so take your choice, old town or more modern district. Personally I'd pick the old town.

The Colon is OK, IMO, if you can get one of the rooms which faces the cathedral. I've not stayed in that hotel for several years and hopefully it has been updated inside. If you like that part of the Gothic Quarter the hotel and its lower-priced "sister" are pretty much central.

We just got back from Barcelona, we stayed at the Grand Hotel Central first and then the hotel Claris at the end. For me it was not worth the £££. The area is great for shopping but again for me I would rather stay in the old town. Service at the Claris was so so and the breakfast room felt depressing as it was in the basement. I would stay here again
The grand hotel central was in a great location, very close to the subway and the old town , if you can find a good deal this may be a good option. I would pick which area you fancy fist and then go from there.
If the issue isn't money then I too would stay at the Mandarin Oriental.

Sorry that should say I would NOT stay here again ( the Claris)

The decoration of the Claris is much more interesting, with an Asian art theme in the rooms and public spaces, but perhaps not to everyone's taste. The location is just enough off of Passeig de Gracia to feel a bit less touristy and put some great eating places within easy reach.
The Colon is in a much busier spot. It's so easy to get around that may not be worth the proximity.
I think the prices are pretty similar, so location is probably the difference.