Well my results with methanol span the last, almost 25 years. I dont' know it all. But we've learned a lot based on our own mistakes, which is why I mentioned all that. I've run-and run successfully the following brands of carbs on a slew of different engines. Rupert, Pro Systems, CSU, J&S, Braswell, Holley, Carter (yeah an AFB converted to Methanol), Predator (hated that one), Quickfuel, BLP, and C&S. Rupert's were always almost spot-on as far at the tune, right out of the box. Can't say that much for the others that I've run. But a good Rupert carb is going to set you back as much as injection, or close, and though the performance isn't a lot different aside from a little better throttle response out of the injection, the simplicity of injection is where it's beauty is.
I won't argue which is better, but I am just stating what has been one of the two best investments in my program. One was backhalfing it and 2nd was going to methanol injection. Between the two, they have paid for themselves many times over. I've been successful with a carburetor as well, and so many others have too. But all it takes is ONE gasket to leak, fill a cylinder with fuel and your raceday is done. Not a problem with injection. Having worked with a few people setting their stuff up, I find it a lot easier to set up the injection than to fiddle with a carburetor's air bleeds, floats, etc. That is why I suggest Rupert, because most of his stuff is nothing more than a phone call, bolt it on, and race. Don't usually have to mess with them much.
Far as some cars not picking any up going to methanol, those are isolated cases...usually big inch stuff (600+) with lots of compression. There have been a few exceptions but by a large majority, I'd expect to see a .25 to .3 improvement in ET going from gas to methanol, with injection being closer to the .3 improvement. It is not without it's problems...BUT once it's on and tuned, it seems to be a lot less problematic.
Think about racing in general. Top fuel, top alcohol, most all sprint cars, and a TON of other types of race cars all run injection, and all of those are basically the same setup....mechanical...it's just stupid simple and it flat works. Indy cars used to run mechanical injection for years until electronic injection became more prevalent in the 1980's, then a few years ago they went to E98 fuel which is available nowhere else but a race track....I want to speculate why they went E98 but I'll keep that to myself. NASCAR also went to EFI but E15 (IIRC) and I speculate why for the same reasons, having to do with "going green".
If the OP wants to hash it back and forth, I would suggest calling James Monroe or Scott Offerman at Ron's midwest office, (killerrons.com) and they'll give you unbiased, realistic, and tell you what to expect from either setup...without you having to spend a dime other than what the phone call costs. Those 2 guys are awesome. George Rupert is too, and I will personally attest to his excellent service, but I got the impression that he is in business to sell carburetors. When I asked him about injection, the subject changed pretty quickly. Nothing against him, that's what he does is carbs, but I wanted an opinion on both. When I called Monroe, I got that opinion and it was unbiased, good and bad of both sides. I also talked directly with Rons out of Arizona and I didn't care for their attitudes but I also know that everyone has a bad day here and there.