You're right. Realistically speaking, they wouldn't, unless the character of the free verb was to their liking. But it's true that most free verb plugins are not great. I wasn't really suggesting that you could shove VSL through any old free reverb. I'm saying that there are very good plugin reverbs that cost a fraction of units like Bricast, and they will probably rival it in terms of fidelity. Try the demos of IK Multimedia's Classic Studio Reverb, Or the Arts Acoustic reverb.
There are some very inexpensive convolution engines out there too. SIR is even free!
Like I said, I did an A/B test between Bricast and Roomverb in Cubase. They came out pretty close. You'd be surprised. I would post an mp3 of the results here, but I'm not sure the guy who created the original Bricast music file would approve.
Look, the fact is that if someone gave me Bricast as an early Christmas present, I'd grab it with a big silly grin all over my face. I'm sure it's a great unit. But there are viable software alternatives which produce amazing results at low cost. [:)]
PS. There's a reverb plugin called Variverb Pro that is available as a free demo. The demo limitiations are actually pretty generous - it doesn't save or recall new presets. Apart from that you can use it as much as you like. It's still quite buggy, but it sounds great and it's up there with the best of them. Certainly, it's the best "free" reverb out there now.