So, let's see here.
The contestants, in order from left to right:
Fournier 2818 EPT v2
Fournier 2818 EPT v1
Fournier 2818 WSOP Breakout
Fournier 2818 WPT
Fournier 2818 Red/Blue (which I'll term as "Flourish" for lack of a better term).
Founier / Congress 2826
View attachment 842613
Manufacturer
Fournier
Price
Varies depending on if you can find them in stock and where. In Canadian funds, expect to pay around $35-$40 for a 2-deck setup.
Feel
The EPT v1 and WSOP Breakout cards are older, and have a more "gritty" or "pebbly" feel. The EPT v2, WPT, and 2818 Flourish cards are slightly gritty, but not to the same extent as the older cards.
The 2826 cards have a slight texture, but are the smoothest of all of them.
All of them feel approximately the same with respect to flex and shuffling.
Looks
The EPT v2, WSOP Breakout, and WPT cards look exactly the same. The 2818 Flourish cards have a larger and thinner pip font. The 2826 cards appear to use a smaller version of the font used on the EPT v2 / WSOP Breakout / WPT cards.
The EPT v1, 2818 Flourish, and 2826 cards use a darker red (aka "security red").
View attachment 842621
Durability
In my experience, the backs have held up well. The faces do appear to wear in that white specks will appear over time in the pips, especially on speedcloth. From a wear perspective, Desjgn Classic Victorian cards show less wear over time in my experience.
Case
The 2826 came in a 2-deck plastic clear case. The others came either in tuck boxes or just in cellophane (no box). Luckily I have some spare KEM/Copag pastic 2-deck boxes.
Overall
I'm a Fournier fan. Of the above, I prefer the feel of the older cards than the newer ones, and the WSOP Breakouts are my #1 card overall. That may be because I cut my teeth on the the Bicycle Prestige cards in the black single-deck cases with the racing stripe back, and they feel essentially the same as the older 2818 cards.
I'm not as a big a fan of the 2826 cards as they are not as textured in my estimation, but I prefer poker-sized cards anyways.