My Thor's are good for as long as they stay dry, May i suggest you go and buy a pair of gortex outers from a snow boarding shop for around £25 to £35 then,as these are roughly around the same price as a good pair of gloves,with the added bonus of being a very thin pair of fully waterproof gloves for when its wet but not cold.also some ski shops sell whats called a gortex inner to wear under ski gloves, that arnt waterproof. if you can find these they tend to be a more fitted glove as they are put on first.you may also want to have a look in the expedition type shops, they seem to sell loads of high tec waterproof gear, that weights next to nowt.seems to be a bit more pricey though.
i like you had the same problem,the gloves i owned were more them warm enough, but when wet were very poor,bought some gortex outers first,then a few months later found out about the inners, whilst walking in the lakes.not looked back since.
Merchant