Hi Mailmaverick,
I just did the BricsCAD free trial. It was the second time doing the free trial in the last few years. The program has it's strengths and weaknesses when comparing to AutoCAD. It's outright better than Acad in some areas in fact (it runs much smoother on my computer for one).
The short answer is yes, it can replace AutoCAD 100% for some users. It's for sure one of the better choices if you want to replace AutoCAD completely, because compared to some of the other AutoCAD clones, the file compatibility between it an AutoCAD is superior* (*This is hearsay but from a reliable source, I haven't had enough time to test that out personally. I myself would keep an AutoCAD LT license active just in case and to create dynamic blocks [see below]).
The long answer: There are a few objective drawbacks to using BricsCAD. For one, block creation is really far behind (You can import blocks from AutoCAD though; perhaps another user can chime in as to whether this creates stability issues or not). Also, to get the best value from the software's pricing scheme, you need to make a relatively large initial investment. This even applies for the 'classic' license. I noticed some features that should be included in the 'classic' license aren't; one needs to get a 'Pro' or 'Platinum' license just to obtain a few simple features. Depending on your work flow and style of CAD, these drawbacks might have exactly zero effect on your productivity, or a drastic effect on your productivity.
After trying the program out for the second time, I wasn't as impressed as the first trial for a few different reasons. 1) The pricing has gotten substantially more expensive (and more convoluted) It's not much more expensive to just go with AutoCAD LT. And 2) It seems like Hexagon (the parent company of BricsCAD) is going down Autodesk's route and focusing on 'flashy' features that nobody will use, rather than refining the core functions of the program.
I might still purchase a BricsCAD Classic license. If the price was 50 - 75% of what it is currently I would have done so already. But instead I am checking out other CAD clones; ProgeCAD is next on my list. It has way more functionality than the BricsCAD classic license for roughly the same price. Whether it is useable remains to be seen.