Hmmm... Not to sure of which is better, the latex or the gut prophylactics. I remember reading that historically the gut condoms were the first available and latex came along much later. Otherwise I have no idea which gives the bigger bang for the buck...LOL. :)
As far as the violin strings go there are two types. The most popular is the "gut core" types where the gut is tightly would to form a string and then the gut core is wrapped in silver, aluminium or gold Less common (and harder to find) are the pure unwound gut strings. The latter are preferred by some very dedicated baroque style musicians who want to capture that authentic period style and sound. Often they will even have their instruments altered to even further affect that early baroque style.