No.
Seriously. It depends on what you're looking to do (as you say, helmets and weapons), what your budget is and how much energy you're willing to put into it. And asking for "what's the best printer" 10 people will give you 11 different answers.
First question : are you prepared to build your own printer (be it as kit or -unlikely for people not having any background in 3D printing, designing and building one yourself) or do you want a ready-made machine instead ?
Buying a ready made printer has the advantage you'll exclude a lot of trial and error, as several brands will need you to use "their" stuff/fillament ect ect Now if this sounds like a vendor lock, it probably is. But it does have advantages too. For example, your printer will always run optimal in terms of temperature, flowrate ect ect as such printers have been optimized to get the best results out of the printing material you're using, so the chances of misprints (and you WILL have misprints, a lot even if you're a bit unlucky) are minimized at the price of higher material price and less flexibility in usable printing material. In the past, I had the issue of optimizing print for lets say "brand A" of PLA filament, getting good results, having to buy extra PLA from "brand B" and using the print settings that were so good for "brand A" would give terrible results on "brand B". If you're unlucky, that may even happen within a give brand of filament by the way.
If you want to combine the printer with a 3D scanner : that too will determine your choice. Stuff like Davinci, Ultimaker and probably a crapload more models offer this possibility.
Some very smart and handy people just go out there and buy the raw parts they need, building their own (which will most of the time be a variation of a reprap printer). A task that's not to be underestimated but you'll have full control over what you do or do not want to do. I do not know all that many who've gone that route. I know even less who got their stuff working in a good way. Not saying it's not possible, I've seen at least one guy who did this and his machine produces awesome results but just saying : if you're not a tech head or lack patience and a certain level of "self inflicted pain" I would not try this. Certainly not for a first-time user.
So you want "instant results", this is not the way to go : in such cases you're better of buying a complete 3D printer in a box. Stuff like the Dremel Idea builder which at least one member owns (and he's very pleased with it).
Or the DaVinci series (vendor lock filament on all non-pro versions I think).
Enough Dineros on your account ? Look at Ultimakers' offerings. Or look at the countless Ultimaker 1 clones on the market, many people are very pleased with them. I've worked with them in the past and they're nice. The closed box also helps to cope with temperature variations, making it better suited for ABS printing. But honestly, even on a self-build printer you can easely build your own enclosure to help keeping the temperature factor under control and it wouldn't cost you an arm&leg either.
On a budget, still looking for decent results ? (like me) : Any of the better I3 or Rostock designs should be right up your ally. These printers can be scored pretty cheap : print quality will vary depending on the quality of the kit and your own mechanical building prowes. Many cheap I3's are Acrylic-based designs, which tends to be a bit iffy in terms of print quality as the material used for the frame isn't the most sturdy stuff around.
I3 kits are also sold in Alu or even full steel frames (P3Steel series), allowing for superior mechanical stability thus enabling better quality prints. Velleman has a very nice piece of kit too (K8xxx series) which has been used at least by one Spartan for a fully printed Halo 4 armor and must be said, it looked fantastic.
Peterthethinker has his 3D printer armor too which looks fab too but at the moment I can't recall what printer he used. Get in touch with him if you want to know more.
Price tends to go up very fast depending on how big your printbox is. So depending on what kind of stuff you want to do (you'll be slicing designs anyhow, at least very probably) the maximum printbox that is provided will be an important aspect too in the choice of your machine. For example, a 2000+ USD Ultimaker prints within the dimension of roughly 220x220x200* or something. A Dremel Ideabuilder does 230x150x140* and costs something like a 1000€ over here. A full steel P3 giant version can be had for 850€ and has a printbox size of 400x400x400*, the 300x300x300* version costs approx half that price.
* = forgot to mention, all dimension are metric and in mm. Just added this to avoid confusion.
Many of the "reprap" designs allow for better printerparts to upgrade the printer ... which you can print out yourself. It's a really strange and utterly cool aspect of 3D printing.
You could do far worse than looking at the site here
https://www.3dhubs.com/best-3d-printer-guide to get a lot of feedback on existing machines, although the feedback isn't always as consequent or even plausible. I've read feedback destroying a certain product/printer for reasons like "bad precission", while knowing that specific model does allow for high quality output when it has been put together correctly. So that says more about the commenters' own mechanical capabilities and not about the printerdesign itself.
Hope this gives you a couple of ideas.