Anyone ever tried 2x100Watt Bi-Amp Vs 200 Watt

I believe I misunderstood your question. For some reason I thought you were asking about vertical bi-amping - 100w for mid/HF drivers and 100w for LF drivers, not horizontal bi-amping - one amp per speaker. So please disregard my initial post.

agree with Kr4. Depending on what you want to achieve, if you are trying to increase SPL then you need to feed it more power. If you are after better sound, vertical bi-amp might give you that.

Done both bridging (Plinius SA100's) and passive biamping. In the latter, I used Monarchy SE100's above 90 Hz and an old Mission 777 (100W) for bass, along with a custom attenuator to accommodate gain differences. This setup took advantage of both amps strengths and fit my budget at the time. I'm not sure a dozen Monarchy's stacked in parallel could have matched the Mission's bass, despite the identical rating. A higher xover would make matching more difficult with amps that aren't identical.

A friend matched a Coda System 100 for bass with Manley Snappers (100W tube) and there was only a slight gain difference.

The other thing that should be considered is that input impedance drops with passive biamping. With a few exceptions, that should not be a problem.

Speaker impedance neither drops nor rises with biamping as a rule. There are few exceptions. If Ngjockey is referring to the input impedance seen by the preamp, that does drop but most amps have such a high input impedance that even halving it still presents a reasonable load for a decent preamp.

Kal