Well you can get it quite low.. But with 3x recharge you'll need to slot some dam/acc HOs to make the most out of your damage output in FA.
Anyway's here's the numbers:
Hasten (70% rech) + 3 SOs (95% rech) + 1 siphon speed (20% rech) -> a recharge of 21 seconds
Hasten + 3 SOs + 2 siphon speed -> recharge of 19,6 seconds
Hasten + 3 SOs + 3 siphon speed -> recharge of 18.5 seconds
That should be the correct numbers for different amount of siphon speed stacked on top of hasten and the rech SOs. You might also want to consider the ranged AoE set with an acc IO (if you dont take the KD proc), would give you 100% damage, 95% acc, 90% rech and 33% end red.
- @DSorrow - alts on Union and Freedom mostly -
Currently playing as Castigation on Freedom
My Katana/Inv Guide
Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either. -Einstein
Many thanks. 21 seconds still sounds like a lot of fun 
The Smoking Demon
Ash/Tar Corruptor
Union
@The Smoking Demon
Also bear in mind several of the AR powers take that tasty Force Feedback Chance for +Recharge IO for some more tasty recharge 
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Also bear in mind several of the AR powers take that tasty Force Feedback Chance for +Recharge IO for some more tasty recharge
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Yeah and with fulcrum, flamethrower and with the epic immob & ignite combo you will have a very nice toon
thePhilosopher Martial Arts/Regen/Fire Scrapper
theRegulator Empathy/Energy/Soul Defender
Total Inertia Ice Blast/Kinetics/Psy Corruptor
Total Inferno Ice Blast/Thermal/Leviathan Corruptor
So I remade my main due to the Tommy Gun unlockable power fitting him perfectly. I went with Kinetics as a secondary as it fitted him better than the other secondarys (especially in apperance).
Now I'm a little excited due to the thought of Hasten + Speed Boost + 3 Recharge SO's/IO's in Full Auto. So with all these three effects, anyone have any numbers for an unnumbery person? My thought was a recharge of 15 seconds.
The Smoking Demon
Ash/Tar Corruptor
Union
@The Smoking Demon