"I am really intrigued with the idea of getting a nice Rolex clone movement and modding the outside in the same way...a unique watch that keeps precise time (+/- 6 seconds per day....max -10/+15 seconds per day, plus hacking) and does not require a safe to store it."
There are a few different rlx 3135 Chinaclones and iirc one in particular stands out and the others fall by the wayside. I have never owned or been inside one and this is from remembering some of what I have read...you might read back in the older posts and see what's what. Besides that, most need cleaning/oiling upon delivery and this is not going to be inexpensive and many/most repair shops will not work on them.
Since there are no spare parts available for these movements, sooner or later no parts = a non-running watch. A few genuine parts may work but genuine rlx parts = $$.
"ETA will likely keep better time than a Chinese clone if you’re that way inclined."
I agree. Many of the Chinaclones of any type can turn out to be junk (putting it politely). China 28xx etaclones are hit and miss and the only parts I have had much luck with are the auto wind assemblies.
Nuc's Seiko advice is a safe route to take and will not start you out on the wrong track. Starting out with a rlx 3135 Chinaclone dud can sour you on the whole experience.
A swiss ETA is also a good choice and since the prices have gone waay up on them you might look for one in a nos or 'like new' watch from the 1980s/1990s at a lower price than a new 28xx ETA movement. Nos ETA etc movements usually need c/o but any competent watch mechanic can work on them. Ask friends and relatives if they know a retired watch repair guy and see if one might still be working at home. That way you will not get the 'doctor price'.
Franchise mall stores/chrome and glass sideshows etc usually charge too much for repairs because they farm the work out and add 40 or 50 percent for their trouble.
'C & G Sideshows' = the average jewelry store that sells a few (mostly quartz) watch brands and advertises 'we repair all brands'. Few will have a repair guy on site other than an employee who changes watch batts armed with a dull case knife and hammer. Ask them what color of 'Rodico' they like best (green or blue) to test their expertise. Ha!
I like blue but my 'specialty' is watch-botching.
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