60 cards vs 90 cards

whats best?

Depends.
But often it is best to tr to minimize your deck so you have better chances in running across the cards you need.

Which gives you less room to be toolboxy.

Then again, decks that burn through cards with alarming speed (some combat decks, for example) might still need the full 90 cards in order not to run out of cards in the middle of the game.

Yeah, it depends on the expected card flow. More "static" decks should be closer to 60 (or ones that depend on some specific combo), while decks which burn through transient cards at a fast pace (combat decks based on non-permanents, many bleed decks) need the full 90 cards in order to not run out.

Also, it's not a binary "60 or 90" question. Sometimes something in between is the right choice. Play with the deck, see how much of it gets used in a typical game, trim it down as much as you can (but not more!)

If there are specific masters (and especially a specific ratio of masters) you want to play, then building a less-than-90 deck is useful. Otherwise, I'm a fan of building 90-card decks. I think notions of "card flow" and "draw improvement" are overstated, and I prefer to bring a full load of ammunition.

BenPeal wrote:

full load

...are we not doing "phrasing" anymore?

I play all kinds of decks: from 60 cards up to 90 cards.
Of course, it depends on the type of deck and on your playing style.
Decks with (or close to) 60 cards will more often show the same drawing results than decks with (or close to) 90 cards.
Quite often I end up with decks around 75 cards.

You have to find out yourself, so give all sizes a try!
Plus, there a PLENTY of successful decks of all sizes in the Secret Library!
(There you can find decks, that virtually play with even less than 60 cards by making use of the "burn option" technique.)