Trundle for Toddler?

Today's obsession is what kind of bed should I buy for my two-year-old who's now climbing out of her crib.

I don't think we'll go for a very cool built-in trundle bed like the one pictured above, but there are some other more affordable ones like this one from target. And it qualifies for a 15% and free shipping which helps.

Or I could buy another Ikea bed to match the one my older daughter has.

Eventually we'd like to put built-in bunk beds in the girls' shared room, but we're a few years away from that. So maybe I should just go with a cheap toddler bed like this one until then.

I thought sorting this all out in a post would help me make up my mind, but I'm still confused.