Official mocks are the best and the closest but the scores in
Experts global mocks are fairly representative according to my experience… if anything, sometimes you can find the Experts mocks a tad more difficult because all mocks are high difficulty mocks.
A small suggestion from my end would be to attempt the mocks under exam-like conditions only. This would ensure that there are less variables affecting your mock scores. In general, that much of a variation between mock scores on tests from any two credible sources (such as official mocks and
Experts Global mocks in your case) should be considered an anomaly and you shouldn't let it distract you.