You have lauded the SDI Deep class....have you actually looked at its contents versus the PADI Deep class?
I don't recall lauding the SDI Deep class. I do recall expressing appreciation for my OW instructor, who told me that SDI Deep only requires 2 dives, but he requires 3, and that he takes all his students to a full 130' on the 3rd dive, so that they can have the maximum experience of narcosis, while with someone competent to get them out if they have trouble.
And, yes, I have looked at the PADI Deep course and see that it requires 4 dives. But, the 4th dive is not required to go especially deep, and I don't recall that there were any particular skills to perform during that dive, other than planning it and executing it.
For myself, I expect I will take the Deep course as soon as an opportunity presents itself (that doesn't require me to make a special trip from VA to FL), regardless of which agency is sanctioning it. If the instructor is certified by PADI and SDI, I'll probably request the SDI version, as I'd rather support SDI than PADI. Hopefully, the instructor will teach me the same stuff, regardless. I've already done 2 dives, to 85' and 89', and was very comfortable, had a good SAC, etc., so I'm not too worried about whether the formal course includes 2, 3, or 4 dives. I just want to make sure the instructor does take me to at least 120', for the reasons my current/previous instructor mentioned. That seems like a good idea to me. I want to eventually dive to see some wrecks and I'd rather my first trip to > 120' be with a solid instructor, rather than an Insta-Buddy.