1.7 CDTI Reliability

[ffzetecs]

Considering a Vauxhall 1.7 CDTI either late Astra H or early Astra I

I do c. 20k on mways so efficiency and reliability are crucial

Have been informed to avoid 1.9 as it's a Fiat designed lump with a host of common problems, but that the 1.7 is a sturdy albeit older unit.

Any experiences?