We also live in AZ and are having pebble interior put in. Everyone we have spoke with has mentioned that the pebbles will most likey block the pop ups. In-floor was our original plan, until we started looking at the cost and decided to go against it thus saving 5-8k on the total cost of the pool.
My MIL has a regular plaster interior and we LOVE what the in floor does with her pool.
Hope that helps...2 different scenarios