My son just turned 2, and he's NEVER liked strollers. Ever. He's been in all makes and models - I used to borrow from friends and test-drive, because I was desperate to be able to have him be in a stroller for more than 10 minutes without pitching a fit.
I plunked him in a Volo last week. It was like I just handed an 18 year old the keys to a shiny new Porsche, lol. He l-o-v-e-s it, and we go on walks (GASP!), and he doesn't fret at all.
It doesn't recline, so if your 18 mos. would sleep in a stroller it's probably not a great choice. My guy doesn't sleep anywhere but his crib, so it didn't matter for him. I love it, and wished I hadn't put so much importance on parent and child trays when deciding on a stroller.
I also got my huge 4 year old one, and he loves it, too. I make him walk when we go for walks here - his chariot is for Disney only - but he hops in his brothers while his brother pushes him. That should give you an idea of how easy they are to push - my 30 pound guy pushes my 48 pound guy all around and up small hills.