Recommend a deck board for me to use

I'm interested in this as well. I'm starting to lean composite.

i've built a few over the years. the standard treated 5/4" lumber is usually fine. BUT, if it will be exposed to south and or west direct sunlight you will need to plan on regular refinishing.
if a pool is involved in the deck area keep in mind that wet feet on it will have the dendency to get splinters - personal experience of me and my kids. i ended up replacing with synthetic deck boards for considerable $$$.

i dont have any experience with IPE. you?

I've used both composite and pine on a few decks. Composite is more expensive, but no maintenance or splinters. Harder to install also. Pine is easier, about half of the price, but will shrink and swell, can get slick and have slime buildup, needs refinishing every couple of years, but looks better IMHO

When you break it down, it comes to cost, whether or not you're willing to do maintenance, and looks

So no one has had issue with the 5/4 x 6 deck boards? I am about to begin this process as well.

I just finished mine with tigerwood. I posted pics on here not long ago. Check em out

Think I'm going to go with 2x6, knowing that I'm going to have to refinish them every year or 2. Not too big of a deck and not sure how long i'll be in this house. It'll likely become someone else's problem in 5 years or so.

Are the 5/4 sufficient compared to 2"?

Excellent. Thats what I'll do. Thanks for the help.

Ipe (ironwood), cumaru and jatoba are all great for decks and will last forever.