As far as using other grips instead of a grip adapter, I would be happy to but I haven't found a grip that does exactly what the T grip does for a reasonable price. In theory, "boot grips" mimic a t-grip/magna combo, but in practice the ones I've messed with feel bigger in my hand and the finger grooves are more obtrusive. The closest I have found is the Pachmayr Compac Pro, but they are rubber and they only make them for a few guns. If someone made a $50-$60 set of wood grips shaped like those Pachmayrs, they'd be on every gun I own.

With regard to 4" revolvers, IMO the 4" M29 is a must own gun. That one I have is brilliant. I'd post a pic but I've already posted several in this thread. The flexibility of the .44 magnum round is just incredible. If you don't handload, buying a 44 magnum is all the excuse you need to get into it. You save money, but also you can load cartridges that will do anything you want from light practice loads to stout personal defense loads to nuclear strength woods loads. Elmer Keith and the Magnum Associates nailed it when they developed 44 magnum.