From what I can see after about 12 hours of wandering through the game newbie-style, reloading is mainly an issue with things that are reloaded one bullet at a time, such as the Cowboy Repeater and the .357 magnum. So far (admittedly, not very far), my single most effective gun was the Varmint rifle given to me by Sunny Smiles and topped with a night scope bought at Chet's. That thing takes down humans, giant ants and bark scorpions with equal ease. I've experimented with the Cowboy Repeater, the .357, the Caravan shotgun, etc., but the Varmint rifle is superior, except against small creatures like the giant mantis nymph or bloat flies where the shotguns' spread effect is more appropriate. But shotguns reload reasonably fast as it is. So, is the perk worth it?
Another question: is it possible to "save" perks for later? There appears to be a distinct lack of useful perks on lower levels, but the menu doesn't seem to offer the option of allocating the skill points without choosing the perk.