Put more space between the trench and your mouth, maybe with a whip? Or water filtration? I used my LB for a long while dry, sometimes multiple trenches a day, and didn't get that. As for recommendations, the Solo is a good choice.
The Solo is such a hassle-free vape I could tell you exactly how to use it over the phone if it came to that. There isn't an awful lot to it which ends up being very good. Fastest advice that you'll most likely ask about: fully charge it when you get it, do 1-2 dry burns at 7 for the whole 12min...
It seems that the "new" charge-and-use model of Solo has a higher failure rate than the older ones, at least from what I can gather here on FC.
Re: serial numbers, I was poking around the beginnings of this thread again and saw a few mentions from people and retailer emails about it, guess...
I really do like TV's first gen products. They look industrial but compared to other mechs they have a flair of their own. I showed off my Ultra setup to a few guys at the local ecig shop and they were all over it. They were even more impressed when I told them I had been using the same atty...
You'll need to pull a little faster with smaller amounts, they'll require less heat overall compared to full trenches. I've had great luck vaping enough to cover the bottom flat part of the trench, up to right to the rails.