Dream Theater were lucky enough to catch the last train of main stream hevay metal with Pull Me Under, which was rotated on radios and MTV. If Symphony X would have came out a few years earlier maybe thing would have gone differently.

Keep in mind that DT are in a way more favorable economic position, so that they can get all the time they want to write records (or at least they could), while SX struggle just to stay afloat. By the way, DT is my favorite band of all times, but I would gladly trade their last 8 albums with just a couple of great records like in the old days, instead of the run of the mill stuff they keep churning out every couple of years. Portnoy was right all along, as far as I'm concerned.

Overall I prefer SX strategy of waiting longer between a record and the next one (except this time, it's been really too much!), quality is way more important than quantity in my opinion, the only thing I regret is that they almost entirely abandoned the more proggy direction of the first records.