Hi Kalev, My first lathe was a Warco GH750 and is still going great, still accurate and never any trouble, and I bought it new in round about 2000/2001. Although looking at the the GH550 you mention, it does look different to the GH750. [which is no longer available] at least not the original one. I did think when I saw your question that they would be similar [apart from the between centers distance ] but they are not If the GH550 is as reliable and trouble free as my GH750 is, then you will have a nice machine. I hope there are others on here that are familiar with your specific model.
Cheers.