If its for normal sports, muay thai is better as it more of conditioning your whole body.
If in your mind is for sparring/deliever awesome killer combos, it will be touch to choose betweern this 2 arts.
As why>>1st.
Wushu can be seperated into many forms, North shaolin,south shoulin,1 is moren in hands/elbows, the other is in legs kicking /groundwork.
Combo also can be delievered in lighting speed. They also hv some special ways of blocking then auto go in for the kill....whahaha, from my experiance, i would choose wingchung.lol.
2nd>>
Muay Thai> Now the muay thai never teach u all the "resisted moves", i know cos i went b4 to the thailand 3mths acdemhy(it was hell.knn@#$%^)
Muai thai also emphisist alot of body endurance, need u to tahan alot of pain.
*Dun say see lik ong bak show then crazy over muay thai, other arts also can effectively block all atacking & deliever those return kills.
|>> 1 of the resistricted move is knee your enemy ribs when u grap them(tat is for point system) the real muay thai is knee the balls,the nose/face...in sg they never theach u de..
As since is the sport, they use point system, touch 1 time then, time up, add up points,, etc
Jus lik bjj> passing guard, then u gv the ppl a knee ride, then go back to gv a choke, its for points or till they tab out.BJJ is more of a submissive sport.
In 1 of the top posting, i see ppl post caporia, i never really see a good asian use that, but only see a noob(learn 1year but can kick alot of ass) using it

the stance he delieve is bloody beautiful, jump here jump there,flip here.flip there, then ALL OF A SUDDEN, A KICK COME OUT OF NOWHERE!!!!!, make the TKD person go to ground.
Fren say cap is a form of sudden atack where u lease expect it.
If u can, krav magar also damm good.i only heard my fren learn, but have not see the power..Its burtal,got some moves lik the malay benja silat, very effective.
Last point, any martial art is
effective if u really practice it hard, hv your ground work good, good body to tahan pain/steminaer.
It hard to say which is best, u can be the best stricker standing learning muay thai.But when VS (street) a guy that know BJJ, muay thai is nothing....
For eg, i learn muay thai, i VS a TKD black belt 3 dan(friendly game) *you must know TKD mostly play defence/far attacks wid leg...go aim their center line/chare in,, then aim vital parts, TKd guy lie on floor.Tat is provided the TDK guy dunno any akido.
When going for any martail arts,you must ask yourself u wan to self defence/street/play points system/???? then go learn, hv to know each of their chariteristic, what is their flaws..(now all add in new stuff as all improving..) then u go learn, b4 any match, hv a clear ans of wat your opponent background,play far distance or short distance. Use combo in long or short distance.. Of cos , u need to hv good steminer, if not, a normal conditioned guy learning any sports b4 will easily ko you..Unless u got bloody good technics lik BJJ...
Play wid your opponent then use your best on your enemy(what they dun know) A normal "game" in bout 2 minutes, u can tell wat he learn...
If in the streets..if for me, i dun care what he lean, i see iron rob i whack the fuck out of him.. see his boones harder of metal rod harder..is not he die or i die..lololol..