I'll acutally answer.
Parliaments give a much stronger buzz. The first time I smoked Parliaments, I actually got kinda sick. Granted, I was kind of new to smoking, but they're strong.
Marlboro lights have the same really heavy toasty/smoke flavor that Reds do, but it's much more tolerable and there's much less aftertaste. Parliaments have a fresher, more tart flavor. You'll find it's a very big difference. Parliaments have more of that chemical/synthetic flavor going on, and since I've gotten really good w/ cigarette flavors I ceased to enjoy them.
Granted, I don't think most smokers notice flavor nuances to the same degree, so it's whatevs.
Plus, Parliaments are like $2 more than Marlboros...
Parliament FF are okay, but very, very heavy and kinda hard to find.
EDIT: misread the OP. thought it was Marlboro V. Parliament, not Parliament V. Marlboro.
Marlboro lights are the best selling cigs. To me, they're okay. They're one of the only two types of Marlboro blends that I like, the other being Marlboro VA Blend. They have a strong aftertaste compared to most cigs, an average buzz,
kind of a quick burn (like all Marlboros), but decent flavor, albeit one you'll have for a while.
Parliaments burn
really fucking fast, and I mentioned the rest above.