I've stayed at Holiday Inn Express at Sathorn and one around Soi 11, and the Holiday Inn on Sukhumvit Soi 22 multiple times.

Hands down the Soi 22 location wins the day with me every time. The hotel seems like a higher brand than a Holiday Inn, imo. The pool is great, rooms are good, and I really enjoyed the lounge when I was bumped and given access. The breakfast was also quite good...but the staff are disorganized and will often try to seat strangers together at tables even if there are other tables open. They are friendly but a bit scattered and probably need some training.

I also liked the location. It's a short walk to the MRT system, taxis are plentiful, massage places and street food around, and it's about a 15 to 20 minute walk to Nana if you like that sort of thing.

I'll stay there again...