Softube's Bass Amp Room is a bass amplifier simulator plug-in, and a cool one at that. Softube has a few different amp simulation plug-ins in this vein that share the same sort of interface. I don't own this plug-in, as I've just used it at the studio that I work at. It comes in all major plug-in formats and for both Mac and PC. I didn't install the plug-in myself since I don't own it, but I've never heard of us having any problems with it. The interface of the plug-in is really cool, as it gives you three different amps to choose from, all with different settings. You've also got controls for your DI signal and a parameter to balance out the levels between the amp and DI. The amps each have a virtual microphone in front of them that you can actually drag and move into different positions, and is quite flexible and what it is able to do. I wouldn't say that using the plug-in is hard, so I don't think there's any need for a manual.
All of the systems that we have at the studio are Pro Tools HD based, so we rarely have performance issues at all one these systems. For this reason, it's hard to say how much processing power the Softube Bass Amp Room plug-in will take up in an LE type of system or something similar. To me I would think that most users would be okay, but since there are so many different levels of systems out there, it's definitely hard to say based on my experience with the plug-in.
Overall, the Softube Bass Amp Room is one of my favorite bass amp simulators to use. It's really user friendly and there is a lot that can be done with it. The sound of it is definitely pretty realistic as far as amp simulators go, although I'm not totally convinced with amp simulators in general, although this definitely seems to be one of the better sounding ones. The interface is probably my favorite thing about it as it looks really cool and is very versatile. I'm not sure if this comes in a bundle or something with the other Amp Room plug-ins, but either way it's worth looking into as a bass amp simulator.