Variants v. Quattro
I totally agree with the comments above on normal sporasubs over the variants, and I can add an extra reason - the footpockets. These are really designed to be worn without socks especially in the case of the quattros, but the normal sporasub ones are best designed for wearing with socks.
Painting fins
Those hawaiian ones look OK. Mine are black, and I learnt a few things on the way....I orignally sprayed them with car paint and then covered them in a layer of fibreglass resin. Bad idea. It all cracked off on the first go where the fin flexes most. The polycarbonate paint is great. It can get scratched off, but dosen't come off from fin flexing (the paint is deigned to be flexible).
Attacks and Radicals
Should have mentioned this, sorry. As a stock fin, I much prefer the radicals. Due to the corrugations, they 'wiggle' a lot less. They are also softer, in fact the softest fin I have used. The only bad point to these fins is the Colour of the upper side. If it had the same colour as the underside on top - I would still be using them. As it is, my wife uses them (on her annual dive....). I like the attacks with rails slightly better as they are a wee bit stiffer which makes them better for spearfishing.
Twisters
They cost me 175 quid from the UK importer. They aren't worth it, and they don't come close to C4s or Mtechnics. I ended up customising mine by recutting the ends to make them stronger. Then they got stolen. :rcard
The rail
This is a pain. I have no idea where you can get hold of the rubber that is used for fin rails. If someone knows - tell us now! I cut and sanded down a rubber seal from a cargo container. I don't reommend it. When I find out where to get hold of the proper stuff, I'll cut my poor efforts off and put on some better rails.
Extra, extra!
I forgot - I used an old pair of Mares Concord fins too, and they were way too stiff too.