Ukraine vs Russian

I have noticed there isn't much activity for expats in Russia. Ive been to Ukraine once for 2 1/2 months but not Russia and I plan on going soon. I know you need an invitation letter and travel visa to enter Russia, but now with the new rules you can stay there for six months. The visa is valid for three years. All you need to do is cross the boarder out, have lunch and come back in for 6 more months if you want.
  So maybe someone from Russia,Ukraine or other expats can talk about why Ukraine seems to be a much more popular destination for expats vs Russia. Maybe there is something I should be aware of before I go that is different than Ukraine?