older are usually better, especially ones with older stranges because that way at least if you get an unbox you dont like you might be able to get a decent price for it

Well, prepare to make a loss. It's practically impossible to profit off opening crates unless you get an unusual. If an item contains high value stranges, the value of the crate will go up, making it more expensive to unbox. 30 and 40 are the only ones with a decent enough profit margin.

Either way, I'd recommend trying to profit off those keys, rather than using them, but I suppose there is a slim chance of getting an unusual, but even then, it may not be good.

i agree with champelliot. you wont break even unless you get things such as white/black paint, headshots part, projectiles reflected etc. using those keys to make other deals is the safer choice. slow and steady wins the race. if you must unbox (cant control yourself) i suggest checking the wiki (http://wiki.teamfortress.com/wiki/Mann_Co._Supply_Crate) and finding the ones that give the best chance of making your money back at least (crate 42 (HS part), or crate 28 (s shotgun) are decent). just do your homework on which crates are good.

I turned dota keys in TF2 to open boxes, just a few. Already traded most of it in stranges I want.. so I just have a few to spare :)
Thanks for advises!

#30>#40>#19>#21>#14>#13>#28>#42>#1>#31>#33>#9>others
Something like this

Originally posted by 12345:

#30>#40>#19>#21>#14>#13>#28>#42>#1>#31>#33>#9>others
Something like this

They'll all result in a net loss though, looking at it objectively. 30 and 40 are the only real exceptions and even then, large losses are possible.

If you buy #19 for 1.33 ref or less and #21 for 0.33 ref or less it will not be loss. Though it's not easy to buy them for that price.

Crate 19s are worth about a key, getting them that cheap would never happen. Let's say it does though:
Let's look at it like this:
You have a 21% chance of getting a Targe (1 ref) (-3 ref if received)
You have a 21% chance of getting a Grenade Launcher (4-5 keys) (+7 ref if received)
You have a 21% chance of getting a Sticky Bomb Launcher (1 rec) (-3.66 ref if received)
You have a 21% chance of getting an Eyelander (1-2 scrap) (-3.88 ref if received)
You have a 5% chance of getting a Hustler's Hallmark (1.33 ref) (-2.66 ref if received)
You have a 5% chance of getting a Tippler's Tricorne (1.33 ref) (-2.66 ref if received)
You have a 5% chance of getting a Schadenfreude (3 ref) (-1 ref if received)
You have a 1% chance of getting an Unusual (<14 keys - >100 buds) (Potentially massive gain)

We'll ignore the unusuals because if you're after them, you'll open a current, cheap as dirt crate.
The crate costs 4 ref to unlock. 1.33 ref for crate (impossible to get) and 2.66 for key (closer to 2.88 at the moment)

You have a 63% chance of making a colossal loss.
You have a 10% chance of making a medium loss.
You have a 5% chance of making a small loss.

You have a 21% chance of making a medium sized profit.

In any case, unboxing crates is really not profitable.

I say get crate #19. I bought my 19s for 1 ref each and I got strange grenade launcher out of one of em.

Originally posted by BROSAMA UMADEN:

I say get crate #19. I bought my 19s for 1 ref each and I got strange grenade launcher out of one of em.

Then that's luck, but in the long run, you'll make a loss.