"Mosfet" covers a wide range of things. Specna Arms EDGE and I think now all the CORE models have a very basic mosfet that just offers trigger protection and better current flow.
If you go up to the Specna Arms EDGE 2.0 models, or the Double Eagle M9xx, then you'll get a fire control system with a lot more options like burst modes.
If that's what you're after, then those are the two that I'd suggest. They also have decent hop units and quick change springs so you can fine tune the power easily, and both of them have Deans connectors. The Double Eagles are a bit cheaper, although at the moment it's a case of buying whatever's in stock.
Or the S65, e.g. https://www.modelsport.co.uk/product/438918