Personally I take GNC Mega Men: Maximum Nutrition Formula, chocolate flavored. I like it because in my quest to find the best supplement I read over and over that a big factor was how much your body actually absorbs. When you put that much stuff into any pill the compression has to be super high in order to make the pills small enough to swallow. As a result the pills sometimes don't completely break down before they are "passed". With this particular product you take two scoops of powder (chocolate or vanilla depending on what your preference is) and mix it with water or milk. I like to go the milk route, chocolate water is a little weird for my palette to process. The result is I feel better when I'm taking it. There's no denying your actually getting your vitamins, which is what a multi-vitamin is all about. The argument comes with the proprietary blend they add and the quality of their ingredients.
As for the proprietary blend, that's going to affect each person a little different. Everyone has a body different from every other body out there. What makes me feel energized may make someone else nauseous. To that point, it also depends what your looking for in a multi-vitamin. Some are looking for simple body maintenance, to keep their heart and prostate in good health. Others are just looking for energy, just a little extra pep in their step. Yet others still are looking for big gains, high protein levels and the such. So be your own judge when it comes to making the right decision for you.
To the argument about quality of ingredients, in so much as GNC takes the business of the lowest bidder. I hate to shatter some romantic ideals that people may be holding onto out their, but
every major business is looking to get their supplies at the lowest cost possible. The ones who don't are called specialties, and they usual operate on a very small scale, their product isn't overly abundant, and generally costs three to five times more than going rate. Lets take a look at the numbers of the top three supplements in this poll against GNC's product:

So you can see what I'm talking about. If GNC is only buying from the lowest bidders with inferior product, what does that say about the other supplements mentioned? It's just become very trendy to hate the big guy in the industry, hell I've been guilty of it myself. However just because a company is big doesn't mean their product is crap. In fact chances are their product very well could be even better than the smaller companies, as they have the clout and resources to leverage lower prices. All I'm saying is don't let people who have no real idea what goes into a product tell you what you need. Your best bet is to try a handful of these products. Take one supplement for a full month, record in a daily journal your experiences. Then after that multi-vitamin runs out take a week off taking nothing, then try another supplement for a month. Continue this process for as many multi-vitamins as you want to evaluate. In fact if you've got the money to burn or can buy several sample packs you could try a multi-vitamin for two weeks, then off one week, then on to the next multi-vitamin. You'll get faster results however I say you'll be burning through money, because you'll have half jars of vitamins laying around, as most come in a one month supply.
The bottom line here is if you want to really know how a multi-vitamin is going to affect you you'll have to try for yourself. In life their are a lot of things that you can purchase based on a web review. However your health is not something to gamble on. If so-and-so give a movie two thumbs up and you end up hating it, you're only out twenty bucks. On the other hand if you buy something you put in your body based on some bloggers review or some fancy packaging you could stand to loose a lot more. Yeah you'll have to commit a couple months worth of work, and by work I mean three minutes of taking the pills and writing down your thoughts, but if you're planning on taking that supplement for many years to come, that sounds like a worth while investment to me.
Just my two cents 
Edited by setotitan, 19 January 2010 - 06:30 PM.