I think the worries about the load response can be completely eliminated by hooking up to a real cabinet. This defeats the load in whatever box you have and have the actual speaker response come into the picture.
Of course, you'd have to have a great speaker to get the best out of it. But it really broadens the options for cabinet response if you have a few good cabs. I quite like the Orange and Mesa 2x12s I have, both with V30s. Not sure about the speakers in the Mesa - I don't think they use the China-made V30s (and the quality of those Chinese speakers are also subject to much debate - but the Orange is a really old one and has English V30s in it.
In that regard, I really like my Fryette PS-2. Have got some good tone out of it running into the IRs. You can completely reduce the volume too, so there's no trouble with the neighbours.
Other than that, I've tried the Suhr Reactive Load and the Reactive Load IR. I hated the fact that the Reactive Load IR has to be powered, the one without the IRs built in is the one to own, IMHO.