I have Maxx 5000?s and a training buddy has Bumper Boy?s. They are both very good and reliable there are differences. The Maxx?s are harder to setup (two bottles, electronics, then bumpers) but to reload all you do is put the bumpers back in place. The BB?s are easier to set up but take longer to reload, so it?s a trade that washes. His BB?s have always thrown longer marks by like twice as far. That might be important.
To me the biggest purchase difference is in the electronics, since BB?s come with theirs and with the Maxx?s you have to add them. If I was only going to train with this style of launcher I would get the BB?s.
If you are going to add something say a winger, now you have to buy electronics for that. I bought my Maxx?s used with electronics so if I add another device I just have to hook it up and I?m ready.
If I had to do it over again I would base my decision on whether or not I was going to have addition equipment.
Oh ya, both get stuff in the hole, dirt, mud, water, snow it doesn?t matter you have to clean them out. The Maxx has about a 2 inch hole it is easier than the little hole on the BB?s and not as critical that you get it real clean.