good choices
About said airsystems, each of them fine systems indeed:
All 3 are expensive, in my opinion more expensive than necessary for a Shocker where regulation already occurs in the Maxflow. A simple Pure Energy or Crossfire would do nicely. Be that as it may...
1. Maxflow--
Advantages:
a. Anyone that owns a Shocker already knows how one works and how to take care of it.
b. Proven winning combination for a Shocker. In fact, it was designed for it in the first place.
c. Great service with SP Europe. (Often service of SP US is spotty: good sometimes, sometimes downright crappy.)
Disadvantages:
a. Sensitive to dirt. But hey, if you're running a Shocker, you're used to disassembling and cleaning stuff anyway and don't mind, right?
b. If you're in the US, which is a non-issue to you, you're dealing with Smart Parts.
c. If any but the latest Maxflow is bought, unless you get that ridiculously expensive ($50+ if I recall correctly) OTP cap with the allen screwed locking ring, there is the possibility of it turning up high involuntarily (mimicking the notorious Maxflow chrono cheat) and blowing your low pressure relief plug and/or your gauge. Yes, this happened to me. It sucks when it happens.
2. Armageddon--
Advantages:
a. Simple design.
b. Light.
c. Extra bottles easy to come by.
d. Can be and is often match anno'd to your gun.
Disadvantages:
a. More expensive than it should be.
b. Bottles easily stolen. You can't prove yours is yours. Yes this happens.
c. Short threading, meaning easily taken off intentionally or unintentionally. Easily solved problem, just screw it back in, although this SUCKS if all the sudden on the break your gun goes "click click click" instead of "pop pop pop" and paint is flying at you RIGHT NOW.
3. Apocalypse--
Advantages:
a. One of the oldest designs in paintball. Hell, it must be worth keeping or people wouldn't have.
b. Old Apoc 3000's can be quickly and cheaply into new 4500's, saving much appreciated money if you go bargain shopping for old/used systems.
c. Can be rebuilt with Mag spare parts which are easily found and not difficult to understand.
d. Can withstand significant punishment and still function well.
In fact, damn near impervious to external damage.
Disadvantages:
a. Bulkier than a substantial number of other air systems.
b. Stiff on/off, which actually may not be such a bad thing when considered that it can't be easily accidentally turned off, but that's your call.
c. Heavy when they were stainless...haven't picked up an aluminum yet.
There are some of the relevent facts. That answer your question? All 3 have tons of people out there that know them well, so if anything goes wrong or you have a question, someone near you will know how to help.