In a nod to LM's posting about Spoon, I'd say Challengers was a "grower" for me. Challengers was not what I had fallen for, so it took me a long time to see its worth. Sorta like Pop.
The first two albums, Mass Romantic and The Electric Version, are infectious, syrupy sweet (but delightfully complex!) pop songs. "Jackie" might be my perfect pop song. For these two, think "Sing Me Spanish Techno" and "Broken Beads" from Twin Cinema.
Challengers continues the departure from their pop past that started with Twin Cinema. More diluted hooks; more deliberate crafting of songs; a seemingly more ambitious album. Think "Falling Through Your Clothes" and "Stacked Crooked."
So, branching out from Twin Cinema... If you have a musical sweet tooth like me, drop everything and get the first two albums! They're both equally masterful pop. Challengers falls more toward the plotted end of the spectrum. Challengers can be flat out dirge-like in places, compared to the first two, but it's good.
You can't go wrong, based on your love for Twin Cinema. I probably listen to all four nearly equally, but tend to prefer Twin Cinema and The Electric Version. Sorry for the essay - hope it helps!