Water-based wood preservatives, are they any good?

For years I've always used solvent-based wood preservatives on any outdoor wood projects and repairs; using products like Protim, Cuprinol, Larson, Panobond etc. They worked well for me and seemed to give reasonable penetration once the timber was dry. In recent times I found that the traditional preservatives have been replaced by water-based (micro emulsion) alternatives. I used one of these (Larsen Universal Wood preserver) at the weekend to treat some boards on an external wall cladding project I'm doing at home. On the plus side it is low odour, quick drying and easy to use, but I do wonder- is it any good? I'd be interested to get feedback from other users, although it seems that there is no alternative nowadays.