Majority of all proxies are recycled, and the sheer intelligence of JaGeX's bot catching software - proxies are irrelevant.
Ever notice they go down in succession? As of right now, you have to find a goldfarming method that has no requirements. It must make the money day #1 if you wish to go with this in the long run.
24/7 run 'em, and get a mule that is on a private IP - not on the same client, and would be ideal if off a hotspot or public WiFi to make the trade.
Discussed this with a goldfarmer who's got a 100 man farm. Once I realized the magnitude of how active you must be to make money off botting, I immediately said fuck that. But with the proper set-up, you can make upwards of 200$ a day. And in random spurts, JaGeX does not ban for 2 days or so... this is your gold mine.
Don't bother with getting combat stats, there's no difference between being 19 combat or 3... There's differences when you play the game legit for a period of time before you get out of their eye. Mains and legit accounts can get away with botting for ~6 months even steadily, but good luck if you just made your account.
This just goes to show there bot software is generally towards new accounts with not a lot of play time. A lot of the older accounts get 2 day bans, due to Mods manually banning them and not being under the eye of the bot catching software. A systematical ban will perm you regardless. Makes sense considering some good accounts just get deleted when others get a 2 day temp. This just proves the theory more so.
tl;dr - It doesn't matter if you gave each and every 40 accounts a proxy, they will be banned just as if you made them all on 1 IP. There's plenty of ways to tie each and every account to one another. If anything, it pisses them off.