Sadly this particular listing is a little misleading. The Matilda II is a contemporary of the IIIE... the one armed with the teeny 3.7cm gun and way less armour than you have listed here. The listed armour here is for much later variants. This gun is not just .3cm smaller than the 2pdr, it is much less powerful (length of barrel in calibres for examaple=lower velocity=lower AP effect)
The PZIII does get some fighting power with the introduction of the Later J model - the upgunned version. with the ?L60? 5cm gun.(not certain of the actual designation atm)
If I get time I will post the armour details of the E tomorrow when I have access to some decent books at work. Wikipedia claims 30mm for this model but I am not even going to attempt to suggest that is a reliable figure.