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If you like MX Brown, Topre are like if MX Brown and rubber dome had a baby.
They're like rubber domes with a longer and softer tactile point similar to MX Brown, but it's at the top of the key travel like a rubber dome. They also have a slightly cushiony bottoming out like rubber dome as well, but without all the flex and squish. They are also a very good for off-center key presses unlike standard rubber domes.
There's not much advantage of one keyboard over another besides key rollover. What's makes a keyboard better is if you like how it looks or feels better. It's very much about aesthetics and personal choice at this point. I haven't tried any of the Alps switches, but I'm sure they're fun. I have a Cherry ML-4100 keyboard I bought on eBay for $14 shipped. It's only 2 KRO, but it has a nice form factor, I like the look of it, and the Cherry ML switches are fun to press. Terrible if you press them off-center, but still fun.
My favorite switches are Topre and vintage MX Black (the smoothest switches available). Topre is what rubber domes should be. Vintage MX Black is smooth and linear and feels nice.
I've tried the other MX switches except white and clear and found things I didn't like about them. Here's a summary; I'll go into more detail/explanations if you ask for it:
Red- Too light, force gradient not steep enough.
Brown- Tactile point isn't useful.
Blue- Reset point is higher than the actuation point.
Green- Extra spring force is wasted on this switch design.
