Surefire is the way to go if you can afford them. You can buy a Solarforce L2 that performs just as well, but the 6P was much more resistant to abuse. Don't have to be afraid of dropping it or denting a part badly, nice shiny hard anodize on those, thick glass, a warranty... Things with warranties are more expensive.
I dropped my solarforce L2, had to buy a new bezel because it dented in and locked the lens retaining ring in place. I've dropped my Surefire 6P hundreds of times, but all threads are still buttery smooth. Push button; receive light.
My solarforce L2 has rarely failed me, only time was when I first got it, had to tighten up the tailcap, but since then, been working just fine. 6P was gifted to me, but I believe it was about $90 new. By comparison, the L2 was ~$50 after buying from a US importer. It was one of the nice ones with matching tail and body diamond point knurling, but I digress.
I would never buy a Mac, but if someone gave it to me, I'd definitely keep it. You can make a PC that runs just as quickly for much less, but the Mac does have very very nice components in it. Name-brand capacitors, quality resistors, PTCs, and well-designed.
I guess what I'm saying is, with so many tools that do so many things so well, just pick or list your tasks first, and choose the best tool for those tasks. If 100% reliability, and bomb-proof are on your list, you might do well to pick a light that not only performs well, but is well made. You could buy a DEFT-X, but unless you need a real LED thrower, you'd rarely use it and you'd feel that it was a waste of money. Can you imagine it paired with a nice scope or binoculars, though? And if your job entailed looking through said oculars at night, the DEFT would be the way to go for the best of the best.
Me, I don't mind saving some moolah and having to tinker with it a bit to get it to work well and reliably. It's part of the fun of the hobby!
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