I test rode a similar bike, Marin Kentfield FS today in 19" and a San Rafael in 17". The Kentfield is basically the same as the San Rafael but with 50mm rise bars compared to 32mm on the San Rafael, fixed stem, and lower end components. Price wise, I think the San Rafael is better buy -- if my dad gets strong and maybe develops better flexibility along with the need for speed (because faster is often more fun), the adjustable stem will come in handy.
I like the riding position on the Kentfield 19" more because the larger frame and higher rise brings the bars a bit higher; however while standing, I don't have much clearance to the frame; the jewels are almost scraping the top tube. The 17" gives me a bit more clearance, but it feels a bit awkward because I'm leaning slightly forward.
As far as the Larkspur, it does feel more like my FX than the San Rafael; the suspension fork brings the bars higher.