A very basic logic vs regex speed test (tries to match min 8 char length, alphanumeric word, that contains at least 1 integer, 1 uppercase letter and 1 special character). Tests 10 mil words by default, modify "tests" value to change.

test.js

(function() {
	var integers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
	var chars = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'];
	var upperChars = chars.map(function(i) { return i.toUpperCase(); });
	var specials = ['!','@','#','$','%','^','&','*','+','='];
	var regex = /^(?=.{8,})(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])(?=.*[!@#$%^&\*+=]).*$/;

	var len, useint, usespecial, useupper, buffer;
	var words = [];
	var start = new Date().getTime();
	var tests = 10000000;

	// Generate buffer
	console.log("Generating buffer of", tests, "test words");
	for(var i = 0; i < tests; i++) {
		useint = Math.ceil(Math.random()*10) > 4;
		usespecial = Math.ceil(Math.random()*10) > 4;
		useupper = Math.ceil(Math.random()*10) > 4;
		len = Math.ceil(Math.random()*20);

		buffer = '';
		for(var m = 0; m < len; m++) {
			if(useint) {
				buffer += integers[Math.floor(Math.random()*integers.length)];
				useint = false;
				continue;
			}

			if(usespecial) {
				buffer += specials[Math.floor(Math.random()*specials.length)];
				usespecial = false;
				continue;
			}

			if(useupper) {
				buffer += upperChars[Math.floor(Math.random()*upperChars.length)];
				useupper = false;
				continue;
			}

			buffer += chars[Math.floor(Math.random()*chars.length)];
		}

		words.push(buffer);
	}


	console.log("Generated buffer in", calcTime(start), "milliseconds");

	// 
	// Validate WORD BUFFER WITH FUNCTION
	// 
	console.log("Starting to validate with string validator");
	start = new Date().getTime();
	var count = 0;
	for(var i = 0; i < words.length; i++) {
		count += validateStrings(words[i]) ? 1 : 0;
	}
	console.log("Completed with string validation function in", calcTime(start),"milliseconds",count,"strings are valid");

	// 
	// Validate WORD BUFFER WITH REGEX
	// 
	console.log("Starting to validate with regex");
	start = new Date().getTime();
	var count = 0;
	for(var i = 0; i < words.length; i++) {
		count += validateRegex(words[i]) ? 1 : 0;
	}
	console.log("Completed with string validation function in", calcTime(start),"milliseconds",count,"strings are valid");

	/**
	 * uses programming logic to see if a string is valid,
	 * @param  {[type]} str [description]
	 * @return {[type]}     [description]
	 */
	function validateStrings(str) 
	{
		var ints = false;
		var specs = false;
		var upper = false;
		var c;

		if(str.length < 8) {
			return false;
		}

		for(var i = 0; i < str.length; i++) {
			c = str[i];
			if(!upper && upperChars.indexOf(c) > -1) {
				upper = true;
				continue;
			}

			if(!specs && specials.indexOf(c) > -1) {
				specs = true;
				continue;
			}

			if(!ints && integers.indexOf(parseInt(c)) > -1) {
				ints = true;
				continue;
			}

			if(chars.indexOf(c) === -1) {
				return false;
			}
		}

		return upper && specs && ints;
	}

	function validateRegex(str) 
	{
		return regex.test(str);
	}

	function calcTime(fromTime) 
	{
		return new Date().getTime() - fromTime;
	}

})();