I am just going to do little short reviews for each Tekken and give a score out of ten to say which Tekken's i think are the best and how this current game compares to the others. I would be interested to hear you guys' views on how this compares to the others too.

Tekken 6
The actual fighting engine is probably the best in the series but there are little niggles that are just too annoying for me to give this game the perfect score. Load Times are awful, online is horrible (cheap players, lag), Azazel, Arena is total crap, i liked the story modes in 5 and 4. I personally like scenario campaign and find it much better than Tekken Force, most of the new characters are good and the customization is ace.
9/10

Tekken 5
Great engine, nice Devil Within, Aracade Battle is great and you can get to Tekken Lord offline, the story mode is brilliant and to be honest the only thing i think is over-done in this game is the juggling- man i hate it. Its not needed and incredibly cheap.
10/10

Tekken 4
They sort of changed the engine here a bit to incorporate side stepping a bit more and environmental damage, in theory its a good idea but in practise its actually pretty weak. The fighting feels slow and i dont get any sense of conviction from the attacks at all. The modes are good in general but with a small roster and in my opinion an awful and difficult tekken force mode make this one of the worst in the series.
8/10

Tekken Tag Tournament
This game feels a lot like Tekken 2 to me and this game is great fun. The tagging is something new and i think its brilliant, i dont know why they havent put it in the later games, escpecially on PS3. The roster is huge and allows you to play as old characters like Jun and Kunimitsu. Tekken Bowl is epic. Dont really have a bad word to say about it, apart from the fact that the disc makes my PS2 sound like a motorbike reving up, but thats nothing to do with the actual game.
9/10

Tekken 3
Fantastic in every sense. Fast, slick gameplay and many other engaging modes. Probably the only Tekken that i enjoy playing the likes of Survival Mode on. The best endings of the series in my opinion and is easily one of the best Tekkens.
10/10

Tekken 2
A massive step up from Tekken, loads more characters and more moves. I enjoyed the endings from this game a lot and its the debut of one of my favourite Tekken characters- Jun Kazama:P Very solid fighter.
8/10

Tekken
A solid fighter and the game that kicked started it all. Theres not many moves on display here and the test of time certainly hasnt been kind to it but its still not bad but sometimes i think its a tad too difficult.
7/10