I ask because logically it might be just as easy to make a watch that knows the length of 48 months to one that knows only the length of 12 minths and gets it wrong one in 4 years. How is the information contained in the watch? I am no watchmaker so couldn't say but it might be as easy to do 4 years
I am nervous about how much it will cost me to have it looked at and who I should give it to (in London) It gains about 5 minutes a month which is way out for one of these I think.
Your's has a couple of things I prefer like the coloured date wheel and presumably it has exhibition back. I do however prefer the earlier clasp which is a single fold formed from the AP initials, the brushed bezel with gold bolts and also the screw down crown (maybe yours has this I can't be sure)
Steel=4, White gold=4, Platinum=3.5 and yellow gold=2.5. Platinum is very hard therefore, not quite as hard as steel but much harder than yellow gold. White gold is hard because of the alloy and White gold and Platinum are often Rhodium plated... Rhodium=6 and is therefore harder than steel.