Samsung's Galaxy S9 is failing to match the S8 in terms of sales.

Samsung Galaxy

Samsung Galaxy

Pre-orders for the new smartphone are said to be down 50 per cent compared to last year's Galaxy S8 as reviewers have literally torn the smartphone apart to see how it compares to its predecessor, as well as its rival, the iPhone X.

Pre-orders for the S9 are down 50 per cent, according to analyst Jeff Johnson of Arthur Wood Research.

Johnson claims smartphone buyers are, "upgrading at a much slower pace as features are falling on deaf ears", and that overall smartphone sales, "are starting to decline at an accelerating rate."

The S9 is already available in Korea where first-day sales were around 70 per cent of that of the S8, according to Yonhap News.

But Samsung is still predicting the S9 will outsell the S8, setting a 43 million sales target for the smartphone, which is 2 million higher than the Galaxy S8.

Techradar concluded that, "Where the S8 was great, the S9 is only fine."

Last week it was revealed that AnandTech had tested the performance of the S9 and found it failed even to match up to that of Apple's two year old iPhone7.

iFixit has posted a detailed teardown of the Galaxy S9, giving it a low repairability score of just four out of 10 - less than the iPhone X's six out of 10 score.

The wiki-based repair site found the glass design leads to double the chance of cracking, while strong adhesive makes it difficult to access the handsets' internal components.

iFixit also found the handset's iris scanner, front-facing camera, IR emitter and proximity sensor are "pretty much exactly" the same as the previous G8 model.

The Galaxy S9 is due for release on Friday March 16.