I had a S4 Elan a looong time ago and a S2 Esprit about 10 years ago.
I had to recommission the Esprit as it had been sitting for several years before I bought it. Once I had done that ( replaced battery, brake seals and flexible hoses, gear linkage bushes, cam belt and tensioner bearing carburetor floats and needle valves and rebuilt the headlamp motors) it was reliable and needed only planned maintenance.
My Elan did need a lot of looking after although some of the issues were there from when I bought it. None of the issues repeated themselves once I had sorted them so a well-sorted Elan should be reliable but will need more maintenance than an Esprit as its service schedules are shorter.
As others have said, driving an Esprit is an occassion. People love the car or at least they do in the States. People give you the thumbs up and smile and take pictures. My S2 wasn't quick but it handled well. had a great gearchange and was a joy to drive. The Elan was also a joy to drive. It always felt as though it was doing its best to help and bit like a (well-behaved) Labrador puppy. Although it's probably not relevant to you, it was the best car I've ever driven in snow. As long as you didn't try to brake and corner at the same time, it just when where you wanted it to, a testament to its good manners. Don't forget that Gordon Murray tried to get the McLaren F1 to have as good a steering feel as the Elan so that shows how good a drive it is.
I guess that none of the above helps you decide but, if you want to know more about how they drive, Harry Metcalfe, who does the Harry's Garage range of YouTube videos, has an Elan and an Esprit and has dedicated episodes to each. They were 2 of the cars of his 20-car fleet that he used over the winter. Worth looking at to get more of an idea about them. He also does an episode each year in which he reviews the cost of running his fleet and what work he has to do to them and the Lotuses neede very little.
I suppose what I'm saying is, try them and get the one you prefer without worrying about how difficult it will be to service. Just get a good one.