V-Tape uses the (real) NAGIII input and the 351 plug. The ATR uses IR's from the 102 + saturation from a different tape simulation (with a flat frequency response).
I don't know if you had a chance to test it, but to me it sounds close to the real thing (after adding a bit of compression). Better then UAD (thin with strange hi) and the anamod (a bit lifeless). The Nebula version does sound a bit more "open" then the real machine in this test and can't mimic the dynamic behavior.
Right now I'm using the r2r Otari 30/499 on the mixbus and like it very much. Subtle, but enhances the sound in a nice way without sounding hyped or overly bright. Also the stereo image gets getter.
Hi Jon, the ATR-102 preset is more similar to the Otari then V-Tape, but doesn't boost the HF as much. After loading it you can click on "stereo" in the kern page and save- it is actually a stereo effect.