Re. the Gundlach you were watching on ebay..
I have had these in 5x4, 5x7, 5x12 and 8x20. Of all the cameras I have owned over the years, they are all without doubt the flimsiest.
Usually the bent brass slides for the focussing just run in grooves in the wooden rails (an early one was brass lined) which together with bellows made of rhino skin make them "interesting" to work with. I think they were well designed and made for doing a specific job in the first few decades of the 20th century, but considering their age now, would not recommend them for everyday use: just as something nice for a change.
The Agfa and Ansco's on the other hand have always been solid, as well as the Kodaks. The latter were made here in the UK under licence by Kodak England. The only 10x8 I now have is the All Metal Kodak Commercial View which is magnesium alloy, but still has rhino bellows!
Also I have a tailboard camera in whole plate. Something like this would be fine for portraits. There is rising and cross front, and a bit of tilt on the back, but it is light and folds up pretty small - the tailboard protects the GG. Also, having a fixed front standard it can take quite a heavy lens. I use it for wetplate. It is pretty rigid and strong despite being about 110 years old.