Heh I' m more of a 8' HO kinda guy, also has anyone tried firing up a 8' HO on a 100w mercury or 70w MH ballast? with a starter I think the lamp currents are similar. You might over drive the electrodes during preheating though so I would do it on some cheap lamps.
@ aaron; i believe if you pry off the black RCD cover on HO lamps you'll get a bi-pin lamp, but I've never tried it. I may try it on the next HO to go EOL at my grandpa's shop. The reason I like HO over slimline is because HO starts like rapid start while slimline instant starts. IS is boring lol.
Plus I like the raw simplicity of the 8' slimline pictured here...