General

Superior, reinforced are a must, last 2 are player preference. Im currently using the 10% min crit sylph ring and its AMAZING, it beats a 21% stat ring anyday. In the past i did use the scarlet+meister ring for the 3 set meister eff, however to do this you need to already have 4 set superior gollux (2 Pendants or belt)

With ur 500505050505% attack and boss u can afford lgr.

IMO: Assuming you are 100% pure f2p, not buying any Extra Pendant Slot, the best set would be trying to replace that extra pendant so you can wear a Tyrant Belt.

So the Superior Set would be.:
Superior Ring, Earring, Pendant, and Scarlet Ring will replace it right here...

Now that way you can wear Tyrant Belt, OFC assuming you can afford it all when the time comes. ._.

So in the end, the best ring would be...
Superior Ring
Reinforced Ring
Scarlet Ring
4th Ring it can be any ring as long it has Potential (most important) and if you can get a high level or a good attack for stars/extra stats.

There is really no point in talking theoretical because the only people who can get most of these are basically a paying player. I use to talk theoretical but in the end, i never get them. Unless you have most/all of them there is no point in talking about it.

Like for example, is CRA + Tyrant + Superior Gollux = best end game equips? The answer is no... You need H2O glove transposed from a Tyrant Glove. That will give you a lot higher stats overall. But, in the end can you get those gloves? They are the basically the rarest to find and in the market since it is a h2o Armor. Super time consuming and not to mention, the Denerio farming when you are finally transposing.
As for DB, the best Katara is a transposed one to H2O from a Japanese Katara, but what are the chances you will get it? I have farmed for the past 1-2 weeks and ended up with nothing, Even if you plan to buy one, it will cost you a ton and transposing it will be a long tedious job... It will make you quit

What about sets that have the same level?

@toto78 damn it would have been nice

[quote=shalazaar]Here's the link that i found explaining how it works http://www.basilmarket.com/forum/2855296/0/is_Lgr_not_as_good_anymore_.html

The scarlet ring will go to which ever set effect u have equipped first..... regardless of level?[/quote]

Nope, just tried on mine, this does not work. I'm afraid the set effects changes as soon as you re-equip a higher lvl set!

Here's the link that i found explaining how it works http://www.basilmarket.com/forum/2855296/0/is_Lgr_not_as_good_anymore_.html

The scarlet ring will go to which ever set effect u have equipped first..... regardless of level?

i still think its lgr, solid, reinforced and superior.
lgr has flat 16 att boost and 3 slots which makes it better than meister and scarlet.
Solid has 4 slots which lets it have 1 more prime scrolled allowed.
Also you wont get meister set since scarlet will always take superior set.

since you wont be getting lgr, crack or meister would be fine