The Marhaba lounges are consistently unpleasant in all terminals. They are only marginally better than sitting in the public areas of the terminals. Since this is for T3, you can actually just buy access to the Emirates business class lounge - it is pricey for sure (excl 5% VAT, $150 per person, $125 if they are Skywards blue members) but the difference in space and comfort is massive.

There is also an Ahlan lounge in Concourse B but I haven't used it - given that the Ahlan lounge is much better than Marhaba (based on my concourse D experience), it might be worth considering.

Ro