You guys are great, thanks for all the replies. I think I'll be ordering the Lemo very soon...or now 
The big difference is price. The Lemo can be had for $37 and the Russian is around $90.
Clearly, you have limited experience with the 91%.
People paid because they are have a noticeably better draw than all the Kayfuns with the exception the new V4. They don't need to be drilled out, which is a common among a lot of Kayfun fans. Material used and build quality is on par with the authentic, so they are priced similar, usually less.
They also enjoy the vast assortment of accessories available.
With that said they are more than year old design and limited compared to what's available today.
I believe the Lemo is a fine performing RTA, but to me it looks like a Kanger Aerotank. Sorry, no offense! ��
While realizing that this supposed to be all about Lemo v Russian 91%, I would highly recommend Aethertech's Orchid. Dual coil, dual air draw, sub ohm capable, closest your get to a RTA to perform like a RDA. Even the Tobeco Orchid V2 clone works as well as the original, easily found for $40.
You can't go wrong with a Lemo. I have both the standard and the drop. The drop has a harder (warmer) vape due to its shorter size. I prefer it to my Kayfun Lite Plus.
That short travel is why I run nano chimneys and short wide bore DTs on my 91%s, for me, I can't find better flavor.It's hard for RTAs to match RDAs in flavor because the vapor has to travel farther to reach the drip tip. You can test this for yourself by placing a drinking straw at the end of your drip tip and tasting the vape. You'll notice how the extra tube length mutes the flavor. The Lemo Drop has less flavor distance travel than the regular Lemo and IMHO is as good as it gets right now in flavor for a RTA.
I'm not looking to replace my RDA's really, just looking for something better than the tanks I have. Sometimes even though I'm home I don't want to drip, and I think this will be perfect for that. Also doubles as a good driving tank
Mine should be here Friday, what coils you building for yours?
Great to hear man. My Lemo is supposed to arrive today if USPS doesn't mess up like they normally do. I tried my friend's Russian and he said it was about half open and it was that weird spot between a mouth to lung and a very restrictive lung hit. I assumed that fully open it could be a restrictive lung hitter. The Lemo is supposed to have great airflow, and while it's not going to be like an RDA, it's still very much so a lung hitter. I can't wait to get this thing in the mail and clean it and juice it up. I've read most of this thread and got some good ideas for how to build and wick it, so it's just a matter of time until it arrives. If I like it as much as I think I will I'm going to go to my B&M and see if they have another, or I'll order one online like I did this time. I'll update this thread once I run the Lemo through its paces a bit.The difference in flavor between my Drop and full sized Lemo isn't night and day but is still certainly noticeable. I would say in all but the most time consuming, away from e-juice bottle situations, I would prefer my Lemo Drop -- if nothing else, for its more compact aesthetics. As for the 91%, of which I own two, the vape experience is, as others alluded to, much more closed off. The Russian is pretty much designed for mouth to lung hits -- which, since I've started using an Atlantis, Lemo, RDAs, etc. feels like sucking sludge through a straw. Since I got my Lemo, I haven't used either of my Russians. The Lemo's draw is pretty much perfect for me -- at it's widest point on the AFC, you can get a really nice, restricted lung hit. Because of the openness, and perhaps other design characteristics, I swear that the Lemo lasts longer between re-wicking and just overall holds up better over time. This is also probably because the Lemo also wicks a lot more efficiently -- I believe it has deeper juice channels.
As for build quality, there's no doubt that the Russian is superior in an absolute sense. The threading is fine and the product fits together really nice. Still, it's not like the Lemo is a beater -- I would say it's almost there. In fact, since the Lemo is considerably cheaper, I would say that it presents a better value just in terms of build quality.
Respectable build quality coupled with a wide open design makes the Lemo my all time favorite RTA up until this point (even compared to other dual coil RTA's like the Billow). Mine NEVER leaks, works amazing with a DNA 40 Ni200 build, and tastes great. I think its kind of funny that a Chinese company was able to come out with a cheap atomizer that essentially outperforms all the batch made, limited run RTA's.
The main reason why Lemo has better airflow, is because the main chimneys larger diameter, the ones you mentioned are too skinny even if it has dual coil setup.
And if you drill out the side holes and the center post 4 holes, then those tanks lose the race by 10 miles in airflow.
Just not true with the Orchid. I have tried them all: Kayfun, Lemo, Orchid. The Orchid is VERY close to the Lemo in airflow. I cannot tell any difference between the two, other than getting a bit more vapor out of the Orchid due to the dual coils.