I was born in the early '70's, so do remember having some Mego Star Trek & Superhero figures back in the late '70's, notably Klingon, Uhura, Spider-man, Incredible Hulk, and Superman. Have no idea where they are now.
IIRC, Mego toys started fading out of popularity in the early '80's - probably because Star Wars, G.I. Joe: ARAH, and other similar toys (in a smaller scale) started getting much more prevalent. Plus, there weren't a lot of vehicles/playsets to go along with these larger Mego figures, so the play value was limited.
However, these have made a come-back since the 200X's. I regret not getting some of the Classic ST figures when they were out with the retro packaging (that looked very similar to the original packaging from the 1970's).
That being said, for some reason I wasn't too interested in these latest offerings - not a big fan of the TV show figures.
Though - the ST figures were not bad - especially the Mirror, Mirror two-pack. However, I just can't get interested enough to buy these. If there were more aliens in the line, I would definitely get a Romulan, Gorn, Salt-Vampire, etc. - however, I would be surprised if the line lasted that long....I just can't see these figures continuing beyond this initial wave.