I had been waiting a long time for Dr. Rex as a VSTi and as soon as this was released I was on it like a rabid dog. But One/Solo goes a little bit further, as we'll soon see.....
GUI The GUI is small and covers three pages. It's a little difficult to read because of the size, but in terms of layout and "coolness" it can't be faulted.
Sound Well, this beast plays rex,rcy, rx2, acidized wav and opf (it's own format) files. The sound quality is top notch, however you'll need to provide your own sounds or get one of the bundles (there is currently a drum-n-bass version with the rex files from the 160db and 260db CDs. There are also plans for a Norman Cook/Commercial Breaks one). These should be good value, depending on your style.
Features The feature set is (almost) perfect for what this plugin does. You load up your loop and have the choice of 2 modes. In loop mode, you send a midi C3 and your loop plays in sync. Lower or rasie the midi note and the loop still plays in sync, but gets tuned accordingly. You can export a midi file of the loops groove (even on acid loops), load this into your host and you can then re-arrange the groove, add fills etc. Neato. There are many controls to modify your grooves as well, including a corking filter. This filter , the amplitude and the pitch can all be modified with LFO and envelope modulation. There's even a further set of controls to map controllers to LFO depth , meaning you can map your mod wheel to the pitch LFO depth to introduce vibrato, for example. Two features that would improve things, though, are file preview in the import dialog box and midi drag-n-drop (phatmatik style) of the grove template into the host - hence the dropped point.
Documentation The manual is comprehensive and easy to read. No problems there at all.
Presets - Not really applicable here and unfair to lose drop points because of that.
Customer Support. Exemplary. Dave Waugh is a regular in the KvR support forums and a stalwart of the vst/vsti scene.
Value for Money Quite simply, this plugin is a STEAL at £30
Stability Rock Solid - never crashes or fazes the host.
I was delighted when this plugin was released. It's a great utility plug which has found it's way into every track I've done lately, and usually more than one instance, too. If you have a library of rex/rcy/rx2/acidised wavs then this plugin is simply a *must*. If you don't, then grab one of the bundles and start building a library :-)