I prefer to worship in smaller, quieter temple. Didn't go in main temple building.
Walk around compound to find few older buildings with great historical architecture. Top half of building is wood while bottom half is bricks. Inside of the building is impressive too with wax figure of famous monks. Very lifelike and frightened me initially when I see so many old monks staring at me while I enter.
There's also a figure of the King that founded and developed Chiang Mai

It's a neat place with many vendors set-up so you can buy food and gifts. I found some neat art there. But it's a wat.... we're not religious people so it's pretty to look at and that's about it. The monks kind of creeped me out a little. It doesn't seem to be very strict on their rules for clothing while visiting. I accidentally wore a sleeveless top the day we went and no one asked me to cover up when I went in the buildings. I still felt uncomfortable though. It's only OK. You should totally visit one while you are in Thailand and I guess this one is OK....although I don't have anything else to compare it to since we only visited this one.

There ar a lot of wats in Chaing Mai but this is one of the prettiest (and most visited therefore). Try 7am for the place to yourself.

Very nice temple, some monks speak english so you can talk about Buddhism and meditation with them. Well worth visiting!