You need to go to an AD and try both if possible. The 5205 (40mm) wears thicker and comes w a pin buckle. The annual calendar layout is more legible as well. The 5396 (38.5mm) is a touch thinner and smaller and comes w a deployant buckle. Both should be the same price. IMO, 5205 is a bit more modern and the 5396 more traditional. You can’t go wrong with either!