Skyteam or Star Alliance
 

I am a member of Golden Lotus Plus programme (of Vietnam Airlines) wich is easy to get the elite plus status, i am GOLD now and from june i will be a part of Skyteam because VNA will join ST.
But I think that it will be better if i change from ST to SA.
I live in Poland, I always fly to Vietnam by LOT and Vietnam Airlines (stop in FRA) I have Aeroplan programme.
But next year i will live in Canada so I will often fly to Vietnam and Poland but I don't what to choose... In Star Alliance, there are too many good airlines, but i have to wait for the Star Alliance Silver status (because I just made an AEROPLAN of Air Canada) account, in Skyteam I can always enjoy the Skyteam Elite Plus status.
In Canada, I will live in Vancouver so it's a Star Alliance hub so I can't entry to a Star Alliance lounge because I will be a Skyteam Elite Plus member :(
My dream is that ST and SA be united, but because of all these reasons, I hvae to choose SA or ST??? HELP ME
And if I want to fly with SA from Warsaw to Hanoi, I have to get 2 stops, but with ST, only 1 stop.
Really Staralliance makes me happy but i don't really want to fly to all the corners of the globe to reach the SA GOLD status

I also fly Vietnam (SGN) to the US (LAX, SFO) a lot.
The problem with Star is: no good connections, especially to the US. I did not check the flights to Vancouver on Star.
One World has the best connections to the US via HKG on CX - also a good airline.

a ok, and which alliance are you using now?? oneworld?

I am using M+M/Lufthansa and AA/OneWorld.
The M+M program is good for paid First and Business. AA is good for economy travel (esp. in the US).
OW is good for Asia/US - CX and JAL are fairly good airlines and have good connections for my usual places (China, Vietnam, Hong Kong to LAX), QF is good for Australia. Europe/US is a problem with the AA program: No miles on BA, Finnair and Iberia have limited routes and AA is plain horrible (think United but worse).

Skyteam is also limited between Asia and the US. Delta just stopped flying to SGN (after starting that route a few month ago). VN does not fly to the US (and their business class is like from the 1980s).

If the OP will be located in YYZ then there are decent *A connections using CA.
And AA does earn miles on BA. The only exception are flights between the US and the UK which wouldn't be a big issue for the OP since he will be based in Canada. Also AA is actually not that bad.

If you're flying between SGN in Vietnam and YVR in Canada, there're several decent options on Star Alliance.

1. YVR to NRT (Air Canada) and NRT to SGN (ANA)
2. YVR to ICN (Air Canada) and ICN to SGN (Asiana)
3. YVR to SFO (Air Canada) and SFO to SGN (United) - one stop in HKG
4. YVR to PVG (Air Canada) and PVG to SGN (Shanghai) - this might not work in the future depending on whether Shanghai will leave Star Alliance

from YVR to WAW the obvious choice would be either LH or UA (with a stop in Chicago and ongoing with LO)

for the status issue, you can try to have a status match into a star alliance program, so you can have access to lounges (if you are matched to gold) and continue to accumulate with Aeroplan.

If you also consider award travel, I have found seats relatively easy to get on LO from Chicago ORD to WAW in Business Class. They seem to offer very decent amount of award seats on that route.

No good connections on Star? UA flies to SGN...

Yes, they have one flight per day which is not non stop. I think what Unterwegs was talking about were more options per day to more places in the US.

I wouldn't be so quick to discount Skyteam as while you don't have the connectability of *A and AC there is still decent departures to both Asia via KE and Europe via KL. Once MU joins there is also a connection through Shanghai.