I enjoy fighting with some elemental effects on my side but they're not always the most powerful weapon I have on hand. Sometimes I like to start with some potentially weaker but elemental gun then switching to a higher DPS variant to finish the bad guys off... particularly with slag weapons (for obvious reasons).
Maybe it's just the fireaxe Pyro in me, but I feel like my weapon switch speed is way slow and not suited to this type of play. Is there any item or skill that I use to bump the weapon switch speed a bit?