I've used Megger meters for years and they definitely seem longer lasting than anything Fluke.
To test one grab both leads and get someone to press the button, if you involuntarily yelp it's a good one
i picked up a nice robin analogue tester of ebay for 15 quid been using it for 5 years now. i have a seaward tester for all my meters and its accurate . have another 2 if it jacks in