Well, I have put a set of these to the test all summer (5 days a week for 6 months), and the verdict is they are just okay. They have reduced range from traditional TCUs making them a little less easy to place. The triggers get very worked by any placement other than pure vertical. I have taken a few falls on each of them, and they don't seem to ever work quite the same after that, but I usually have to tweak them and lube them up to make them work right again.

I was a devout user of aliens forever and I too wanted to find a more bomber replacement. They are pretty good, but not quite there yet. BD C3's are way burlier and fit into the funky spots a bit easier.

As a few other reviewers have stated - the trigger is the biggest problem with these cams. If you load the unit in a horizontal position the trigger cables get super worked, hopefully this will be fixed soon! But, I have hammered on them for a while now and they still have great action. The narrow 4 cam head is great and fits snug in tight spots, I think a little better then a BD C3 of a comparable size, plus they cost way less than the BD units! Super light, you will notice a difference from other units, trust me. I found the #4,#5 & #6 to be kinda floppy and don't use them much. The smaller units have replaced my Aliens and my C3's! Overall great value, get some!

The very first batch of had a few which apparently got grease on the kevlar holes prior to gluing. The kevlar is fine. Send it back to Metolius and they will make it right for you. I've been climbing on mine for a couple of months now and they are great. I have two sets of Alien Hybrids and there is no comparison on the quality - the Master Cams are burly, well made, and function perfect. Is there still a rare time when I pull out one of the Alien Hybrids - sure, just until Metolius shifts Offset production from the Ultralight TCUs to the Master Cams.

As others have said, the quality on these is superb. They look/feel solid and the action is a little stiff, but feels right...until you break out the #5 or #6. Then things get wobbly. Especially with the #6. It's kinda comical or cartoon like when you reach up to place it, pull the trigger, and it flops to the right. You re-adjust, pull again...and it flops to the left. Think trying to push like polls of a magnet together. It seems like this is due to the length of the stem.The #1 to #4 feel great, so I would just go with the smaller sizes of these cams. I only have #1-#6, so I don't know about the 0 sizes, but they should be fine if they're anything like #1-3.

I got a 0 and 00. I like having 4 lobes in such a narrow head, as well as Metolius quality. Ooutstanding fit and finish. I choose these smallest units over my black and blue Aliens. And they make a great complement to the smallest C3s. Beyond these sizes, however, I'll stick with TCUs and Aliens. The trigger mechanism is a bit over engineered and has too little slop. A bit more extra trigger cord would allow the lobes to function more independently, creating safer placements. And the cable to the trigger bar is poorly placed. It will kink when loaded over a sharp edge, at least in the blue and yellow sizes.

These cams work well and feel nice. They are very light and make nice placements for the most part as well. Over all I really like them most of the time. My only problem with them so far is that they are not that durable. If you have them bent over at all in a weird placement or anchor or take a whipper onto them they get bent up pretty easy.

good cam for price. not the best though

I've got the #1 and #2, and I like them. The action isn't as stiff as on C3s, which I prefer, and the unit is flexible without being floppy or having a bigass sheath on it. They place solidly, more solidly than TCU's, in my opinion, by virtue of having 4 lobes. Metolius reports the range to be exactly the same as TCUs, and Mastercams are only marginally heavier - a tradeoff I'll take for single stem flexibility and 4-lobe stability.

Well I love the way they fit and I actually have found the trigger to be just fine. The action is very smooth and I prefer a four lobe cam in most small placements. The down side for me was that my partner took a small fall on the purple 0 and the mill stop sheared completely off and the piece blew. Was it because of the way he placed it?? I dont think these are rated to be placed as a passive piece and maybe he had it under cammed but the description might have you believe that the mill stop could handle a fall while placed passivley, which I never wanted to do anyways. I'd be intereseted to know if this happened to anybody else.

I bought a few of these cams last year to augment my older set of CCH Aliens. I've only used the blue and orange sizes (#1 and #3) so far, and they are very similar to their predecessor. As before, they have an internal spring which gives them a narrow head width. The action is pretty smooth, but maybe has more resistance than many other cams. The thumb loop is a generous size, and is easy to clip a biner into when aiding. I've been psyched for the kevlar cord in the cam heads, because the thin wire used in Aliens always got bent in weird directions, making the action much worse. My only gripe is the color coding. I think they are matched to the Metolius TCUs instead of the CCH Aliens (which probably makes sense). This gets confusing when having both on the same rack. But if you already have TCUs, then this would be a good feature.

I was so stoked about the new "safe aliens" then I pulled the trigger and the kevlar cord came unglued from the cam head. Not unsafe- rather unusable. If they only had metal trigger wires they would be perfect. Don't bother unless you want to lose them on your first climb. Expect to see these stuck everywhere this summer.
Bummer.