I've had two Spyders RTLs, a 2019 and now a 2024. I've also had a Tri Glide (2021), and a Lehman Trike conversion on an Ultraclassic. Believe it or not, I liked the Lehman trike conversion better than the Tri Glide, but both were similar.
The Tri Glides ride more like a bike in a straight line than a Spyder, but the ride is very harsh. The Spyders are much smoother and easier to ride as soon as you take a turn of any kind. I do miss separate brakes (Spyders only have a brake pedal stock) and I prefer the normal shifting on a Tri Glide. But the Tri Glide ride is HARSH... Yes, I had to say it twice! I also felt less stable at fast speeds on the Tri, as it always felt that if I had to turn quickly at speed, I could tip it (mine had the Harley stability system, but still felt iffy).
The thing not mentioned, both my Spyders felt a little squirrely, especially at first, I attributed it to oversteering, and it got better but still... On my 2024, I put a BajaRon Ultimate Sway Bar ($300ish total) - WHAT A DIFFERENCE! It is now rock solid, turns so much better, and just feels more stable. No comparison, it totally handles better and safer than a Tri Glide once I put the new sway bar on. If you test ride, and you should, and you feel the Spyder "roams" slightly, realize that it likely does not have the upgraded sway bar fitted and that only gets much better.