latewood, The medium base still require a ballast. I looked at those too and thought you could just throw 'em in a regular 'ol screw in socket but it won't work. At least not the ones I saw with a medium base. Let me know if you find out something different!

And yep ZE you need more concentrated light. You can buy some 23 watt cfl's for about $6 a piece in daylight spectrum and the clip on sockets for about $5. I have 4 of those and 2 43 watters and they put out some major light. Not like a mh but my plants are what I call 'stumpy' cause they're so short and compact. One is 4.5" tall with 6 nodes already!! Got another one that's a little over 2" and it has 4 nodes! So amazingly close growing. Stems are getting hefty too to hold the 8 pound buds I'm planning on...ha.