We have reviewed, owned and perused several Royal Oaks ref. 5402 "Jumbo". As you know, the ref. 5402 "Jumbo" was the first Royal Oak to be launched in 1972 fitted with an ultra-thin calibre 2121 —a masterpiece of 'haute horlogerie'— that changed the world of sports luxury watches forever.

Royal Oak purists tend to never considered buying a Royal Oak ref. 15300 as they feel they are betraying their true love for the ref. 5402 "Jumbo". However, we feel that the ref. 15300 is pure perfection and a robust Royal Oak with a quick-set calendar feature that makes it very desirable. The ref. 15300 is fitted with calibre 3120 which is called by some AP enthusiasts as "one of the greatest automatic movements ever made".

The case diameter is 39mm like on the "Jumbo", however, the ref. 15300 is thicker —than its predecessor— at 9.4mm. The watch wears a little bit smaller than the "Jumbo" as the proportions of the case and bezel are different, regardless that the case size is the same.

This watch just like any other Audemars Piguet Royal Oak is fitted with a beautiful solid link integrated bracelet. The bracelet has the unmistakeable AP grainy brushed finish with some polished areas at the end of the links and around the top and bottom of the center links. The bracelet is very solid and comfortable, however, the clasp is not my favorite part of this bracelet. The clasp is a double push button double folding clasp with AP shape blades on both ends of the interior of the clasp. We personally prefer the old school ref. 5402 blade clasp with fliplock, that happens to feel more sturdy and more comfortable.

The dial in this watch is a "Grande Tapisserie" (waffle pattern) in deep blue with white fonts. Depending on lighting conditions, it will almost look charcoal gray. The dial comes with white gold applied baton hour-markers and white gold Royal Oak hands with luminescent coating. The luminova is not very powerful and since the coated area in the hands and markers is very thin you don't get much brightness. Additionally, the luminova will wear out within a few hours after you go to bed. Not a big deal, just wanted to documented for those 'luminova lovers'. The calendar wheel is 'off-white' almost a very light ivory with all the numbers in the newer AP font with serifs opposed to the old school font in the 5402 and the 15202.

The movement is just gorgeous and quite accurate. This one has only lost 3 to 4 seconds a day —which is still under COSC specs— during the first week of daily wear.

Since this watch comes with a sapphire crystal case back you can admire the calibre 3120 through it. It's just gorgeous! The movement thickness with module is 4.26mm and a total diameter of 11¾ lignes. Frequency of balance wheel 3,00 (=21’600 alternances/hour) Hz, Bi-directional automatic winding with a 22K gold monobloc rotor fully decorated with the crest of the Audemars and Piguet families, 40 jewels, 60-hour power reserve and 280 parts, which IMHO is pretty impressive!

The Royal Oak ref. 15300 is actually more comfortable than the original Jumbo ref. 5402 and a perfect watch that matches all types of outfits—dressed down or suited up. Something else worth mentioning about the Royal Oak, is that is very understated and most of the time it flies under the radar unless you are near a serious watch lifestyler. Another clear advantage of the ref. 15300 over the ref. 5402 or the ref. 15202, is the quick-set calendar feature fitted on calibre 3120.

For those of you that always wonder whether the Royal Oak is suited for water activites, we can confidently say that there is nothing classier than relaxing in the pool with a Royal Oak and Vilebrequins.