We've just been discussing this. Not HTSE specifically, but small exchanges vs RCI. Here's the gist of what I've found the last few years:
The way exchanges work (you did say you were wondering how the exchange process works) is basically this. You "bank" or deposit your weeks with an exchange company, meaning they now "own" your week(s) that year. What you have is a credit in their "bank". So you look for a week to apply your credit to, and when you find one, you "cash in" your credit and get a week somewhere. You can find a week a couple of ways. First, the exchange companies usually have websites where you can see the current inventory (some only let you see it after you deposit a week) and pick from there. If you don't see what you want, you can get them to do a "custom search" where they just start calling resorts in the area and time you specify to see what they have. Sort of "hi, this is ABC exchange, do you have anything available for exchange June 1-7 this year? No, ok thanks". dial again "Hi, this is ABC exchange...". So they try to find you something. This is a bit iffier, as you can only get what someone has.
Our current experience is with RCI (the largest in the industry) and RTX, an exchange owned by Festiva our resort company.
1. RCI is huge. They have a lot of "inventory", which are units and weeks that have already been deposited with them and are available. They get deposits from most resorts, so they have a lot. You can often find what you want just by looking online (after you deposit your week). The downside is they have this thing called "trading power" which rates your units by location, reputation of resort, supply of weeks from this resort vs demand for weeks there, and how far in advance of the give week are you depositing your weeks. So, for example, we only get 90% of the full value of our week now because we're less than 9 months from the date of the week when we deposit our July 2020 week. So a bit complicated, and they are a bit expensive.
2. Smaller exchanges are a bit more flexible, and maybe easier to deal with. RTX, for example, doesn't do that "trading power" nonsense, it's straight week for week depending on season. So I can exchange my Red week for any Red week in their inventory, or that they can find. But we've had trouble getting them to find anything, but we just booked the Florida panhandle for July 4 weekend, so not too shabby. And they are usually a good bit cheaper. BUT. They have very limited inventory. Online they mostly only have available weeks at resorts Festiva owns, and that's not many. So while RCI has lots online already in inventory, every exchange we've ever done with RTX was a custom search.
Which way to go? We're trying RCI this year, we'll see how it goes.