It has been quite a while since I purchased Quantum Leap Spaces, a 24-bit, true stereo convolution reverb by Eastwest and I just want to mention how much I love this plug-in. Now I almost always use this plug-in in every piece of music that I work on as I could easily emulate various spaces at a very minimal computer resource. Instruments just come alive and clear and there is no muddiness or artifacts in the reverb. Also, there is quite a number of halls and space emulations that one can choose from, with variable mic positions. Some have instrument-specific configurations as well which is really, really nice.
Check out this downloadable plug-in at soundsonline.com.