But ur limited in tdk rules in terms of fighting. But in street fighting tdk is deadly. TO sum it all up i would take tdk over thai that's just my opinion but u can never say one discipline is better than the other cause each person is unique.
Just wanted to throw my two cents in - I've gone against black belts in TKD before, and was forced (yes forced) to do some TKD while I was on a tour in Korea. TKD IMHO looked flashy, but was not practical. I've seen black belts get crushed by students of other arts and in street fights.
Take a look at the first couple of UFC's - hell UFC 1 & 2 even. Back while it was one art vs another. TKD didn't do too well.
Ken Shamrock vs Patrick Smith
Shamrock wins by submission due to a heel hook at 1:51.
Patrick Smith vs Ray Wizard
Smith wins by submission with a guillotine choke in 58 seconds
Point here being, Smith didn't win his matches with TKD
I've got to say though, if you seriously spend a lot of time with any art, you deserve props and respect. I enjoy watching TKD demonstrations, but I've got to say that I'm definitely not impressed by the practicality side - especially if the practitioner spends most of their time working towards competitions for TKD. Muay Thai on the other hand - regardless of what you do or don't practice you've got to admit its brutal, and effective. Even more so on the street since half the time, if you cut someone with an elbow they want to give up at just the sight of their own blood.