my experience with Mr. Beer is more like Mr. Yeast. since you cannot get the beer off of the yeast after primary fermentation, the beer picks up off flavors from it. to make a quality beer, you need a secondary fermenter. the secondary allows for the rest of the yeast to settle out and the flavors to blend and mature without sitting on top of a couple of lbs of sludge. to simplify I was considering a six gallon conical fermenter, this combines a primary and secondary by allowing the yeast to be drained off the bottom without disturbing the beer. it also helps prevent infection by keeping air away from the beer, all you do is connect a co2 line to the top of the fermenter to replace the liquid you drain off. alternatively you could store the co2 given off by the fermentation for this purpose.
another issue is bottling sucks, plastic or glass it makes no difference to me. it takes up too much space and too much time. by kegging in corny kegs you reduce both. you can keep beer in a secondary for a month or longer without spoiling, and you can carbonate 5 gallons of beer as fast as you can chill it. if you cannot fit a 5gal corny into your refrigerator, they make 2.5 gallon kegs too, even though they are pricey. so you have a batch of beer in your conical fermenter ready to bottle. what you do is sanitize your transfer hose and keg(s). open up the valve at the bottom of your fermenter and drain into sanitized keg. Close keg. apply co2 pressure to keg while shaking (rocking). Chill keg. serve. brew new batch and repeat kegging process when keg is empty. if you find that you go through more than five gallons of beer in less than 2 weeks, either you need a two keg operation with a ten gallon fermenter or help with your alcoholism.
this is more expensive to set up than Mr. beer, but the more care you put into your beer, the better your beer will turn out.
plastic conical fermenter ready to go $170
kegging system with two kegs and 5lb bottle of co2 $225
propane burners start at $40 for cast iron and $100 for stainless
20 Qt stainless steel pots start at $12 and go up
the rest of what you need are usually found in your galley.
for a 5gal batch of beer the ingredients run between $20 and $40 depending on what style of beer you are making