My first stay at JW Marquis was this January and we was in lounge I can told you simply answer - I think they are maybe equal.
In JW you don't have family with kids area you have only buissnes area wher you cant take food. In GH you can order at HH coctails in JW only alcohol.
Breakfast I think is little beter in JW, but later in day service is better in GH. In GH you have small balcony for smoking area.

What I don't like in JW - we was at HH in lounge, all staffs was very friendly our odres gin&tonic was very strong and next glass came w/o any asking.
After HH they came to our tables and ask if we are happy answer was yes, then they give us cards with tripadvisor links and name of staf, that we write positive coments on website.
This kind of advertisment I don't like, this never happen in GH.