Here's my take on things, though most and many good points have already been raised by posters above. Note that you asked about the ARC4+ vs modded ARCs, so I'm not going to talk about stock ARC LSL and LSHs /ubbthreads/images/graemlins/smile.gif
Modded ARCs vs the ARC4+ (formerly known as LS4)
Modded ARCs
Pros
- Generally better for collecting
- Can be customized--you can often specify how hard you want the LED driven, or what type of LED, for example. So you may go "give me a small light that is as BRIGHT as possible, with no concern whatsoever about runtime and heat" /ubbthreads/images/graemlins/smile.gif
- Unique and rare
- Can add glow paint and tritium markers (which last 10 years)
- Can easily swap the optics--you want throw--Fraen--you want more flood--NX optic
Cons
- No warranty, though in some cases, modders will offer to cover whatever issues come up (and most modders are fantastic in this regards)
- Usually only one or two brightness levels (which may be fine, depending on your intended use)
- is likely not as efficient when compared to the ARC4+ (again, depends on the mod)
Stock ARC4+
Pros
- Temperature and "tint" regulation/monitoring
- Fully adjustable 16-level brightness
- uC (microprocessor) for behind the scenes control
- Machined reflector (matter of preference)
- Lifetime warranty from Peter et al.
- can accept a number of different batteries (when new body tubes come out)
Cons
- Not as unique (well, within CPF, that is)
- Costs a little more compared to most mods
- ARC4+ is bigger and heavier than the standard LSH/LSL body
- Since the design is quite robust (lots of stuff epoxied in for better shock protection), this light is very difficult, if not close to impossible, to mod
I have both an ARC4+ and Jets22's mod of an LS and a 1xAA bored out twisty tailcap. I love both lights--the workmanship on both is awesome. So really, you're in a win-win situation. For either lights, you can always buy one and then sell it to by the other. Personally, I use my ARC4+ more, mainly because I know that it is much easier to replace, but then again, that's just me.
In many cases, modded lights are brighter because there are less "restrictions" or constraints. For example, a car analogy is probably pretty close: most stock factory cars must be suitable for a wide range of drivers, from the fast lead foots to the Sunday drivers. So it wouldn't do to have the engine tuned for pure performance only--hence, stock lights. In this class, you get different types of cars (sports vs sedans), but they all try to, in general, cater to a wider audience.
Now a modded light is like a modded car--you can generally do whatever, but there's a tradeoff. Make the light super fast? Sure! You loss runtime. Make the car faster? Sure, you wear the engine more and generally use better/more gas.
So again, it depends on your likes and intended applications. Hope that helps /ubbthreads/images/graemlins/smile.gif