There is a used InterMec on ebay right now... A T-IV engine provides more torque and is easily arguably the top choice. However, a nice 2110, or a 2332 is a Mustang killer. The 2110 will spank a boxer and the 2332 will shock any 911, except the turbos. You should stay with, or outrun all 80s 911s until it comes to top end.
If you are talking daily driver, where are you? Does it rain there a lot? The side curtains are passable if you don't have a bunch of rain. If you are in LA r AZ, it's definately cool. If you live in cold weather, you want to be sure you have your heater system sealed up good. Most of us SpeedsterOwners are more performance and tune-it ourself oriented, so we avoid airconditioners. The fact is that an airconditioner with dual carbs is a tight fit to work on. But, if you are going to have it all new, and let someone else wrench on it, who cares!
Here are my thoughts. (Keep in mind I know little about where you are, how long your commute to work is, if you are business casual or in necktie and wingtips 5 days a week.) I lean toward a 2110. Go for the airconditioner if it's a daily driver and you have hot summers. If you are going new, live with the sidecurtains, and learn how to seal them up. In the rainy season, get two sponges and a coffee can. I've learned to wedge the sponge in the corners of the sidecurtain and they work fine. I dump the coffee can when I arrive, squeeze the sponges, and carfully close the door, refitting the sidecurtain. When I get back, I pull the towel out of the package tray, blot the seat and jump in. It's livable. Hey, I have other daily drivers, one is kinda luxurious and I still drive the Speedster on a lot of days.
If you prefer the very nice roll up windows, buy a slightly used Intermec... you can find them. A guy wants $25,000 for one with 5000 miles on it. He has the paperwork showing he paid $40,000 for it two years ago. Basically, he is taking a huge hit. If he would have driven it 10 years, he would have been OK, but two years and 5000 miles is a hit.
Welcome to SpeedsterOwners, we are an opinionated bunch. A lot like a family, we fight among ourselves, but don't let anyone cross our Speedsters! That's when the family pulls together as we all have a dog in the fight. 8) Happy motoring.