Hello welcome, good choice I'm biased though. The s turbo is the name given to the European models where as the jap versions were abbreviated to s/tb so if it's a jdm listed as s turbo but says s/tb at the back dont worry.
They share 90% of the parts from the impreza undrrneath engine transmission etc. So essentially it's an impreza wrx engine 2.0 tubo unit producing around 235bhp
Jdm cars ae better equipped with more electrics and ac as standard and you may be lucky enough to get some nice jdm aftermarket bits.
They don't have low range boxes so if it's going to be used a lot off road bare that in mind. But I've never been stuck and have managed to plow through quite muddy fields.
Gearing is slightly shorter too.
As for the sti version I'm not so sure a bout rhe 1st gen foresters but I assume it's the same as the rest of the sti range.
Better seats and slightly different interior, sti struts springs and roll bars, so will sit lower and ride stiffer, more power and uprated brakes bigger wheels to accommodate the bigger brakes. Slight cosmetic changes on the outside, body kit etc.
Don't hold me to this as I've never seen the 2001 sti foz but thats usually the case with the uprated sti parts,
Anywaybif you have a link to the cars feel free to post up so we can take a peek