I think the problem here is the answer you are seeking is not per se knowable in advance. The, shall we say, therapeutic window inherent to the rather caliente cocktail you are proposing is narrow. It could be a great time. You could wake up 5 days later with a hefty bill for a herd of alpacas being delivered presently to you wherever your blackout bender happened to end but your phone GPS - luckily for you, local EMS, and that kindly elderly Peruvian couple from the craigslist now sailing off alpaca-free into a nice retirement - did not.
This shit is serious business and happens, I read about it on a forum once or twice.
I would say that with your impression of a hefty tolerance and such large preordained doses, the risk of unintentional commodity livestock transfers increases to a worrisome extent.
Consider poly-GABAergic dosing to have a more multiplicative than additive effect. I.e. alcohol x benzo 1 x benzo 2 x benzo 3 and at substantial doses regardless of a major tolerance = ???
If you have a "regular" dose of one or more of the benzos, start near there, maybe a bit less. If unsatisfactory, ease into whatever you intend on taking more of. I mean there is a range within which ample GABAergia is enjoyable or not. You're not banging midazolam looking to skirt the threshold, you're celebrating - right?
