+1 what Driftwood said. I have the Star Lubrisizer and the pneumatic cylinder to provide continuous and consistent pressure to the lube reservoir. Nothing else comes close to the speed and simplicity. I've also switched to the "tropical" blend of SPG, which is a little harder.
To fill the lube reservoir, I have a tiny heating pot my wife bought for me at Target - like a miniature crock pot that holds about a pint. I put the SPG in there and melt it, then pour into the reservoir with a small ladle. Works great. I read an article a number of years ago that Dave Gullo (maker of SPG) used the method of melting SPG to fill lube reservoirs, and found it worked much better than cutting up chunks to drop in.