I'm in a similar position to the OP - but I'm shooting a springer. TX200 around 11fpe.
Over here in the US, the Nikko warranty is a little sketchy now that Legacy Sports stopped importing the Diamonds (as far as I know). So it makes a used purchase worrisome.
So if using a springer - does the Leupold advice hold true still? And what is meant by 'harder to use'? Also is the Mk4 x35 that Simon is referring to a custom model of some kind?
Thanks for the info - learning a lot.