I'm all for standard bowls. Let me tell you why...
With standard bowls, they can really serve you well. In most cases, yes they do leak juice on the stem but every bowl except for the phunnel will do that. The advantages are that you don't have to use much mo'assel so that you don't waste, it doesn't require lots of heat, and they are very cheap. Standard bowls always do the job best for me.
With a phunnel, you usually need to use a good amount of mo'assel and coals as well. Now don't get me wrong, the bowl works wonders with holding the juices and keeping the flavour nice, but as others have said ash can get down your stem or on your grommet (mostly depends on hole pattern and if you don't get it right the pull will be terrible because the foil will cover the hole.) Also, lots of time mo'assel will be wasted with a phunnel and I like to know that I got the most out of my session.
I've never used a mod so let's move along to the Vortex. Sure it's a nice bowl but it has 2 MAJOR flaws. 1.) The 4 holes in the cone CAN become clogged and it's a pain in the @$$ to clean that out and 2.) Why in the hell did they have to make the stem on the Vortex so damn wide!?!?!? This really makes it frustrating to use as it's hard to keep air tight, and that's a key factor in your setup.
Just my two cents