From 94 to 96 you have two choices in the 850: The normally
aspirated engine or turbo (also called a high pressure turb). In 97,
the GLT comes with a low pressure turbo (the normally aspirated
and high pressure turbo engines remain). Above applies to U.S.
market (several other engines in other markets).

We own a 95 850 wagon (normally aspirated) and 98 S70 T5 (high
pressure turbo). The 95 is a bit slow and, as mentioned, getting
onto the highway can be difficult.

I can also say, if you test drive a turbo you will want one. The turbo
would be the engine choice for me (either light pressure or high pressure
models).