Advice for replacing failed BoxSter Engine.

[CyBoxter]

I have a 2000 Boxster 2.7L Manual; this was a UK registered car that was exported to Cyprus as a used car. A few weeks ago the engine failed. So I am looking to import a used or a refurbished engine.

I have found, through online searches, a few used engines in the UK. One shop, Volks-apart, can fit the updated IMS retrofit for me and gives me 3 month warranty for the engine and one year for the new IMS (uprated (ceramic) bearing to the intermediate shaft in their terminology). I assume they are referring to the LN Engineering product.

I was more interested in a refurbished engine. I was told me that the only thing that fails in such engines is the IMS, so I will be safe if I replace it. Is this the case: only the IMS failure can cause catastrophic failure in such an engine?

Taking into consideration that this engine will be shipped to Cyprus the 3 month warranty will be very hard and costly to exercise. Obviously, I am very worried about the possibility of the engine failing again soon. What are the chances a used engine to have serious defects given that the IMS has not failed?

I will appreciate any suggestions and recommendations because I have very little knowledge on automotive engineering. I have been reading a lot since the engine failure and I am now semi-literate, which might be worse!