I've been vaping since the first commercial vape (which was like a soldering iron in a glass globe lol) but desktop units still have warmup time... the only advantage is that you can vape with a lot of people on one bowl.
I use portables (pax fv and cera eo) almost exclusively now, but my old friend the herbalaire 2.1 is still with me, it's such a well designed tool I can't imagine parting with it.
I think you're referring to the BC Vaporizer, which was introduced in 1994. (Wow! It's changed quite a bit.) It wasn't the first commercial vapourizer though, that was Eagle Bill's Shake and Vape, which he started selling in 1992.</pedant>
One cause of throat and chest issues with some vapourizers is a short unscreened air path. Combine this with a craving for thick clouds and you have a recipe for bronchial irritation. To relate this directly to the Pax, soak your mouthpiece in enough ISO to cover it for 15 minutes. Shake and remove, then notice how much particulate matter there is, and also the size of the particles. This is just what got stuck to the MP. Imagine what got to your throat and lungs. Also, these are just the largest particles. Aerosol-sized particles form the nucleus of the droplets that make up the clouds you're pulling into your lungs. In other words, thicker clouds contain more potential irritants.
I'm not trying to pick on the Pax. It is by no means the worst offender for this, but it is not particularly good either.