There are four options- crosshair (D), microprism (C?), split (B?), and matte (A). For some reason the price of the splits has gone through the roof in the last year. Must be someone snatching them all up? Anyway, unless you want to spend $125 or more, the matte is the one reasonable to obtain- $35-60.
Brightness is close to the Maxwell. As with Maxwell,s the split Mamiya screen is slightly dimmer, slightly coarser fresnel than the matte.
Using a split on a TLR presents a unique problem if you are doing close objects at wider apertures (portraits most likely). You need to put the focus object in the center of the screen to use the split. Then you reframe. No problem, eh? Well, if hand holding the TLR you often reframe by moving the camera and .or your body in ways that are more extreme than with an eye level camera or a camera on a tripod. So it's easy to end up out of focus in the negative because of the reframing the split demands. Something to think about.
In general I find a matte screen works best for me and how I work. But others love the splits. The matte Mamiyas are the best value these days. Oleson is close, and considering that he cuts to size, etc. possibly the best deal. Maxwells are, well, if I had the money, they are the best but maybe not 'worth' the jump in cost? Your call.