I'll take the side of the Etha on this. I wanted a good allrounder marker that could be customised to whatever setup i require. I play woodsball so its important to be able to do that.
I found that on the own the Etha is reliable little marker. It can take a lot of **** you throw at it. Water, mud, hard ground etc. I have seen an Etha go underwater come back out and still shooting the paint. ( although the paint was going everywhere because there was water in the barrel)
So with my one Etha i have 3 setups
No extras - Just a plain Etha. (I use this if i ever want to play some airball, or if i am not playing woodsball or milsim)
CQB - Etha + EMC Kit + Magpul Grip + Dye Izon Sight + LED Torch + Laser + Rotor ( With speed feed and low cap shell.)
Woodsball - Etha + EMC Kit + M16 Stock + Magpul Grip + Laser + Rotor (with speed feed & high capacity shell) + Remote Line
I tried other similar markers, Axe, Etek 4, Luxe, DAM, I loved them all but they limited having rails. The DAM was lovely but i couldnt justify the £900 cost when i could have an Etha and 3-4 different setups. The only difference is the First strike capability.
Overall i always suggest having an etha, even if its just a second marker, they are cheap and cheerful and very reliable.
I guess it all depends on exactly what you play and what kind of player you are.