Re: Boosters
bryant, I would not approach it like that. You are not buying something that you do not need, just the opposite if the design requires it.
A designer, unconcerned with price/cost, has a short but important list of attributes that their can must have. Included would be:
Safe Operation
Proven cycling
Suppression of Sound
Accuracy
Flash
Materials to meet requirements
Weight
Length
Wear on Host
Longevity/duration (value)
some might consider
Full Auto
Ability to swap threads
Repairability
Easy of Cleaning (rimfire, non purging)
Ablative delivery
The Neilson attends to "Proven Cycling" and "Wear on Host." If you had a Colt 9mm Rifle, or say an MP-5, both with static (non moving) barrels, the weapons cycling happens independent of any effect brought on by the suppressor. And there is no host wear as a result. No moving parts. Some pistol barrels are fixed as well.
Now on a Glock, where the barrel moves, the slide moves, there is an active barrel and the suppressor's weight must be considered. Too Heavy and cycling can be erratic. Each and every handgun is different. What to do? Well, a super light can will not be "felt" on some hosts. These are usually operational cans that are expected to see one clip maximum and need to be small enough for a pocket. Yes, I know TM makes the Poseidon, but I have a problem with aluminum envelopes, wipes that touch the projectile and the idea that ablatives need to be anything other than lithium grease (LG stays put) and needs a proprietary replaceable end cap. Cans like this are not meant for standing int he field and banging through 100 rounds. Can they do it? Yes. Will they be as quiet as a large volume can? No. Different requirement. In any event, no Neilson needed, even on a reciprocating barrel.
http://www.awcsystech.com/products/suppressors/titanium-abraxas-9mm/
Anyway...Neilsons and heavier cans..
One uses a Neilson and "tunes" it by selecting the right spring to insure reliable operation on their particular host. Any fool designer can "over power" the Neilson to slap that slide right back to insure operation. In fact, many pistol cans have Neilsons that do just that, they insure operation by wracking that slide back. Talk to your can maker and see if they actually care what make/model your shooting and if they have tunable Neilsons and a host of spring weights to balance out the system. Interestingly, I only buy Neilson cans from companies that offer a "static end cap" so that I can take off the Neilson, screw on the static end and thread it on a subgun. You want broad wear surfaces on your Neilson. Whereas one may not ever need to clean their centerfire can, always clean and grease your Neilson. A good Neilson is a gem.
One last thing, there are a good number of 9mm makers, since your going to pay $200 and hopefully be able to keep your can for a lifetime of use, take the time to see a broad and deep number of offerings. Definitely Osprey, TiRant, Triad, Hems at a minimum. And get a quality barrel, a cheap barrel on your Glock is a real set back.