I'll tell you that I made the jump to Deathbrewer's stovetop PM method and have noticed a HUGE difference. To be honest my extract brews weren't all that great save for one IPA. I haven't had a bad PM brew yet (3 batches).
The best part of what he does (brew in a bag-BIAB) is that you probably already have all the equipment you need to do it. It will most likely take a little more time waiting for the mash, but in that time you could be cleaning, preparing carboys, and of course, having a beer!
As I read somewhere, its like drinking OJ from concentrate and then going to fresh squeezed. Some would disagree I'm sure, but I've loved the switch and will probably try BIAB all-grain as soon as I can afford a larger kettle.