I went to Danang Vietnam last year for a side trip. It has nothing on Pattaya and Pattaya is a far better option. The bar scene is crap and restaurants are ok but nothing great. I did some serious walk arounds and the bars during the daytime have no customers. At night, some night street food opens up and someone always sells local beer for around $1 USD per glass but that isn't in a bar. On the promenade they have several eating places but you have sit on those crappy small kids like chairs and low to the ground. Anyone over 100 kilos will fall straight to the ground. The food is OK but not cheap and quality compared to Thailand is so so. Accommodation was ok and around $40 AUD per night which is around 1,000 baht including breakfast, mid range 2 or 3 star hotel.
Some things were very good though. The promenade walk is great and better than Pattaya. It is longer, well paved and there are TOILETS which Pattaya has never had, plus it's safe also. The Vietnamese are out there at 4.30 to 5 AM exercising as was I. I am a walk for exercise person and I loved doing that before the sun came up. The other thing I like is that some of their small 7/11 style shops had table and chairs outside (not the kid ones) and you could buy a cold can of beer for the equivalent of 20 baht per can. On a hot day it's great sitting out there having a few cheap beers.
But the over all comparison to say Pattaya, I still choose Pattaya over Danang any day.