I'd also pretty much made up my mind to get an Elise. I'd test-driven one a couple of years ago and really enjoyed it (and getting in and out isn't that bad, I basically use the same technique I use to get in and out of a car with a cage).
So a couple of months ago, when my wife decided to buy me a car (!), we went in with the intent of looking at that and the Cayman S (and if it was convenient, which it ended up not being, a M Coupe). I re-test-drove the Elise, and still liked it.
I went with the Cayman S for a few reasons.
First, when we were looking, it was with the intent of replacing a day-in-day-out daily driver. I can deal with a certain level of unreliability, but if the New Car wasn't available for some reason, I was going to end up driving our truck or our old CRX Si, neither of which appeal to me all that much. It's not so much that I think the Elise would be unreliable (the powertrain seems stout), but the local Lotus dealer has a terrible reputation for service. So putting "slightly unreliable" and "iffy local service options" together seemed like not the best plan. If I lived near a better Lotus dealer, things might have been different. Or if we'd planned on adding the Elise to the pile rather than replacing a car with the Elise, that might have changed things, too. (As it turns out, we kept the M Roadster the New Car was supposed to replace. Ah, well...)
Second, when I asked to see the trunk of the Elise, the one we opened up was quite wet. Like, the owners manual was mildewed. That's one thing I just can't abide: like a boat, the water always belongs on the outside. I freely admit that's a personal pet peeve. Our Elise-owning friend says that it's a known problem, it's something like if you park the car downhill -- or is it uphill? -- and it rains a lot, the trunk's not unlikely to be wet.
Third, my office is 220 miles away from my house. I only go to my office once a week, in general, but that's around 3.5 hours each direction, and I go up, work a full day, then head back the same evening. I've driven a 993 racecar on the street (it had tags and insurance) about six hours total in one day, and a 944 S2 and M3 racecars (again, with tags and insurance) maybe five hours total in one day... and I could do it, and I could even go for longer, but all of those were getting kinda uncomfortable near the end. I wanted the New Car in part to liven up the commute, and while I think I'm pretty hardcore, I had to admit the possibility that I'm not that hardcore.
So all together, it was Cayman 1, Elise 0. If any one of those things had been different, it might have ended up differently.
I'm enjoying the Cayman. I figured that no matter which I chose, I'd end up thinking about how the other half lives!
-Steve