I have flown both quite a bit and own the Odyssey with a Cheetah SP (150N). I fly off 450ft grass runway and take off for both is about the same. (The Feibao Dolphin S /Pilot predator 2.2 is also another one to consider - same airex construction and same pricing)

Here's a basic comparison:

Assuming same engine, servos, etc.

Odyssey is faster
Odyssey has more wing area - floats a lot more (needs crow for landing)
Both with KE with ease but Odyssey needs a little more speed
Odyssey has a little more room to add accessories (2l smoke, etc.)

T1 is stronger but a little heavier (airex vs traditional fiberglass/resin construction)
The Stock electric gear is from JP which is quite good (I bought those for my 2.2M Flymodel Viperjet and also for my Odyssey) (I have had very good luck with the JP retracts - my big 3.5M Viper from Pilot also has JP retracts)

Size:

Odyssey is a little longer and wider (91" vs 86.5, 86 vs 75.5")
Price is about the same retail - for me it was a little cheaper as the Odyssey was available at Nall and I got a set of those JP gears for $ 350 from China. The highest speed I have got on the Odyssey is 192MPH with a small dive.

Good luck.