diff --git a/docs/moment.md b/docs/moment.md
index 0885910e0..b4203bcac 100644
--- a/docs/moment.md
+++ b/docs/moment.md
@@ -141,7 +141,7 @@ See the [formatting guide](formatting.html) for more about the string-outputting
 | RFC 2822             |                | `toRFC2822()`    |                                                                                                                                                   |
 | HTTP date string     |                | `toHTTP()`       |                                                                                                                                                   |
 | JS Date              | `toDate()`     | `toJSDate()`     |                                                                                                                                                   |
-| Epoch time           | `valueOf()`    | `valueOf()` or `toMillis()`      |                                                                                                                                                   |
+| Epoch time           | `valueOf()`    | `toMillis()` or `valueOf()`      |                                                                                                                                                   |
 | Object               | `toObject()`   | `toObject()`     |                                                                                                                                                   |
 | Duration             | `diff(Moment)` | `diff(DateTime)` | Moment's diff returns a count of milliseconds, but Luxon's returns a Duration. To replicate the Moment behavior, use `dt1.diff(d2).milliseconds`. |
 
diff --git a/package.json b/package.json
index 3902c47a5..8c5e0f824 100644
--- a/package.json
+++ b/package.json
@@ -45,7 +45,7 @@
     "fs-extra": "^6.0.1",
     "full-icu": "^1.2.1",
     "husky": "^0.14.3",
-    "jest": "^21.2.1",
+    "jest": "^22.4.2",
     "jest-cli": "^23.1.0",
     "lint-staged": "^4.3.0",
     "prettier": "1.7.4",
diff --git a/src/datetime.js b/src/datetime.js
index 17d2fc92c..5e5030115 100644
--- a/src/datetime.js
+++ b/src/datetime.js
@@ -340,7 +340,7 @@ function quickDT(obj, zone) {
  * * **Week calendar**: For ISO week calendar attributes, see the {@link weekYear}, {@link weekNumber}, and {@link weekday} accessors.
  * * **Configuration** See the {@link locale} and {@link numberingSystem} accessors.
  * * **Transformation**: To transform the DateTime into other DateTimes, use {@link set}, {@link reconfigure}, {@link setZone}, {@link setLocale}, {@link plus}, {@link minus}, {@link endOf}, {@link startOf}, {@link toUTC}, and {@link toLocal}.
- * * **Output**: To convert the DateTime to other representations, use the {@link toJSON}, {@link toISO}, {@link toHTTP}, {@link toObject}, {@link toRFC2822}, {@link toString}, {@link toLocaleString}, {@link toFormat}, {@link valueOf} and {@link toJSDate}.
+ * * **Output**: To convert the DateTime to other representations, use the {@link toJSON}, {@link toISO}, {@link toHTTP}, {@link toObject}, {@link toRFC2822}, {@link toString}, {@link toLocaleString}, {@link toFormat}, {@link toMillis} and {@link toJSDate}.
  *
  * There's plenty others documented below. In addition, for more information on subtler topics like internationalization, time zones, alternative calendars, validity, and so on, see the external documentation.
  */
@@ -1506,19 +1506,19 @@ export default class DateTime {
   }
 
   /**
-   * Returns the epoch milliseconds of this DateTime
+   * Returns the epoch milliseconds of this DateTime. Alias of {@link toMillis}
    * @return {number}
    */
   valueOf() {
-    return this.isValid ? this.ts : NaN;
+    return this.toMillis();
   }
 
   /**
-   * Returns the epoch milliseconds of this DateTime. Alias of {@link valueOf}
+   * Returns the epoch milliseconds of this DateTime.
    * @return {number}
    */
   toMillis() {
-    return this.valueOf();
+    return this.isValid ? this.ts : NaN;
   }
 
   /**
@@ -1640,11 +1640,13 @@ export default class DateTime {
    * @return {boolean}
    */
   equals(other) {
-    return this.isValid && other.isValid
-      ? this.valueOf() === other.valueOf() &&
-          this.zone.equals(other.zone) &&
-          this.loc.equals(other.loc)
-      : false;
+    return (
+      this.isValid &&
+      other.isValid &&
+      this.valueOf() === other.valueOf() &&
+      this.zone.equals(other.zone) &&
+      this.loc.equals(other.loc)
+    );
   }
 
   /**
diff --git a/src/settings.js b/src/settings.js
index b135ae724..7f786448f 100644
--- a/src/settings.js
+++ b/src/settings.js
@@ -3,7 +3,7 @@ import Locale from './impl/locale';
 
 import { normalizeZone } from './impl/zoneUtil';
 
-let now = () => new Date().valueOf(),
+let now = () => Date.now(),
   defaultZone = null, // not setting this directly to LocalZone.instance bc loading order issues
   defaultLocale = null,
   defaultNumberingSystem = null,
diff --git a/test/datetime/invalid.test.js b/test/datetime/invalid.test.js
index 16c8060a6..c185b490f 100644
--- a/test/datetime/invalid.test.js
+++ b/test/datetime/invalid.test.js
@@ -39,7 +39,7 @@ test('Invalid tell you why', () => {
 });
 
 test('Invalid DateTimes return invalid Dates', () => {
-  expect(organic1.toJSDate().valueOf()).toBeFalsy();
+  expect(organic1.toJSDate().valueOf()).toBe(NaN);
 });
 
 test('Diffing invalid DateTimes creates invalid Durations', () => {
diff --git a/test/datetime/transform.test.js b/test/datetime/transform.test.js
index 6116ef3e1..85cd35cde 100644
--- a/test/datetime/transform.test.js
+++ b/test/datetime/transform.test.js
@@ -18,8 +18,23 @@ const dtMaker = () =>
 //------
 // #toMillis()
 //------
-test('DateTime#toMillis() just does valueOf()', () => {
-  expect(dt.toMillis()).toBe(dt.valueOf());
+test('DateTime#toMillis() returns milliseconds for valid DateTimes', () => {
+  const js = dt.toJSDate();
+  expect(dt.toMillis()).toBe(js.getTime());
+});
+
+test('DateTime#toMillis() returns NaN for invalid DateTimes', () => {
+  const invalid = DateTime.invalid('reason');
+  expect(invalid.toMillis()).toBe(NaN);
+});
+
+//------
+// #valueOf()
+//------
+test('DateTime#valueOf() just does toMillis()', () => {
+  expect(dt.valueOf()).toBe(dt.toMillis());
+  const invalid = DateTime.invalid('reason');
+  expect(invalid.valueOf()).toBe(invalid.toMillis());
 });
 
 //------