personaly I've found jackets that convert into a gilet to be a pain in the arse and won't bother again. main reason being that when you need to donn the arms it's impossible to do so without taking the jacket off… bit of a design flaw, sicne you need to connect the arm/gillet zips and try doing it one handed… no chance.
(offending jackets = Endura conversion, Gore Phantom, Gore Complete, Sugoi something..)
so in spring/autumn I stick to a nice lightweight gilet over a jersey as a staple item, and donn a proper waterproof (eVENT)jacket when it gets wet enough to warrent it.
otherwise for proper winter riding I stick to the Gore Windstopper jackets as above (Phantom, Complete) and they are perfect until it gets realy wet and cold, and then the eVENT jacket comes out to keep my toasty….