Do people who have experienced both lifestyles: hunter-gatherer and not, tend to choose the hunter-gatherer life style?
The example that came to mind is https://en.wikipedia.org/wiki/Bennelong
Is he an exception or the rule?
It's quite common for foragers (AKA hunter-gatherers) to want to continue their foraging lifestyle. There are foraging peoples who lived alongside farming neighbours for over 1,000 years, foragers who are part-time farmers or herders, foragers who work as labourers for farming/herding neighbours, and foragers and forager-farmers often choose to continue their traditional lifestyle instead of moving to modern cities and towns. Bennelong was not exceptional in preferring to continue his original lifestyle. Foragers don't always have a choice - if their land is taken over by others, they can be unable to continue to live as foragers, instead living on reservation rations, or work as labourers for the new landowners, etc.
However, this doesn't mean that forager lifestyles are usually seen as superior. People who come from farming backgrounds or modern industrial backgrounds who experience forager lifestyles will usually return to their original lifestyles. Just as foragers who live alongside farmers tend to continue being foragers, farmers who live alongside foragers tend to continue being farmers.
There have some exceptions to this general conservatism, where foragers invested more heavily in farming because new crops became available (e.g., as maize spread through North America) or farmers abandoned farming (e.g., when the horse became common on the Great Plains, and the nomadic horse-based Plains Indian cultures developed).
One example of foragers who live alongside farmers and interact with them closely are the foraging Efé people of the Ituri forest in the Democratic Republic of Congo. They trade with their farming neighbours, the Lese, exchanging honey and meat for cassava and other crops, and tobacco and cannabis. They will also work as labourers for the Lese, usually paid in food (and sometimes tobacco and/or cannabis). The food they obtain by trade from the Lese can be an important part of their diet, sometimes about 1/2 their calories. The meat the Lese obtain by trade is often the majority of the meat in their diet. Their relationship means that both peoples can get items they want without needing to change their lifestyle. (The Efé and other foragers in the Ituri forest sometimes grow one crop: cannabis. This is largely confined to planting seeds at their usual campsites, and involves little care for the crop after planting.)
Further reading on the relationship between foragers and farmers:
Spielmann, K., & Eder, J. (1994), "Hunters and Farmers: Then and Now", Annual Review of Anthropology 23, 303-323. Spielmann, K., & Eder, J. (1994). Hunters and Farmers: Then and Now. Annual Review of Anthropology, 23, 303-323.
Graeme Barker, The Agricultural Revolution in Prehistory : Why Did Foragers Become Farmers?,
Quaternary International Volume 489 was a special issue on the topic of "Forager-farmer transitions from East Asia to Sahul: Regional and Global Perspectives". While all of the papers are relevant, the two most useful might be Alistair Paterson, "Once were foragers: The archaeology of agrarian Australia and the fate of Aboriginal land management", pp 4-16, and Benjamin Smith, "The last hunter-gatherers of China and Africa: A life amongst pastoralists and farmers", pp 121-129.
Peter Rowley-Conwy and Robert Layton, "Foraging and farming as niche construction: stable and unstable adaptations", Phil. Trans. R. Soc. B 366, 849–862. http://doi.org/10.1098/rstb.2010.0307
One thing that often comes up in discussion of the relative merits of foraging and farming is the time required to make a living. It is often claimed that farmers work longer hours. This does appear to be the case, at least sometimes:
However, sometimes the opposite appears to be the case: